diff --git a/estimage/problems/__init__.py b/estimage/problems/__init__.py
index f32beb5..f23ea06 100644
--- a/estimage/problems/__init__.py
+++ b/estimage/problems/__init__.py
@@ -1,5 +1,6 @@
 import dataclasses
 import typing
+import collections
 
 import numpy as np
 
@@ -10,14 +11,17 @@
 @dataclasses.dataclass(init=False)
 class Problem:
     description: str
-    affected_cards_names: list[str]
+    affected_card_name: str
     tags: set[str]
 
     def __init__(self):
         self.description = ""
-        self.affected_cards_names = []
+        self.affected_card_name = ""
         self.tags = frozenset()
 
+    def format_task_name(self):
+        pass
+
     def add_tag(self, tag):
         self.tags = frozenset(self.tags.union([tag]))
 
@@ -45,7 +49,7 @@ def _numbers_differ_significantly(self, lhs, rhs):
 
     def _create_and_add_card_problem(self, card):
         problem = Problem()
-        problem.affected_cards_names.append(card.name)
+        problem.affected_card_name = card.name
         self.problems.append(problem)
         return problem
 
@@ -58,7 +62,7 @@ def _treat_inconsistent_estimate(self, card, computed_nominal_cost, recorded_cos
         if computed_nominal_cost == 0:
             self._inconsistent_card_missing_estimates(problem, card, recorded_cost)
         else:
-            self._inconsistent_card_differing_estimate(problem, card, recorded_cost, expected_computed_cost)
+            self._inconsistent_card_differing_estimate(problem, card, recorded_cost, expected_computed_cost, computed_nominal_cost)
 
     def _card_has_no_children_with_children(self, card):
         for child in card.children:
@@ -75,9 +79,11 @@ def _inconsistent_card_missing_estimates(self, problem, card, recorded_cost):
         if self._card_has_no_children_with_children(card):
             problem.add_tag("childless_children")
 
-    def _inconsistent_card_differing_estimate(self, problem, card, recorded_cost, expected_computed_cost):
+    def _inconsistent_card_differing_estimate(self, problem, card, recorded_cost, expected_computed_cost, computed_nominal_cost):
         if expected_computed_cost < recorded_cost:
             problem.add_tag("sum_of_children_lower")
+        if recorded_cost <= computed_nominal_cost:
+            problem.add_tag("estimate_within_nominal")
         problem.description = (
             f"'{card.name}' has inconsistent recorded point cost of {recorded_cost:.2g}, "
             f"while the deduced cost is {expected_computed_cost:.2g}"
@@ -98,3 +104,34 @@ def _analyze_inconsistent_record(self, card):
             return
 
         self._treat_inconsistent_estimate(card, computed_nominal_cost, recorded_cost, expected_computed_cost)
+
+
+class ProblemCategory:
+    name = "generic"
+
+    def matches(self, p: Problem):
+        return True
+
+
+class ProblemClassifier:
+    def __init__(self):
+        self.not_classified = []
+        self.classified_problems = collections.defaultdict(list)
+        self._categories = dict()
+
+    def classify(self, problems: typing.Iterable[Problem]):
+        for p in problems:
+            self._classify_problem(p)
+
+    def _classify_problem(self, problem: Problem):
+        for c in self._categories.values():
+            if c.matches(problem):
+                self.classified_problems[c.name].append(problem)
+                return
+        self.not_classified.append(problem)
+
+    def add_category_type(self, cat_type: typing.Type[ProblemCategory]):
+        if (name := cat_type.name) in self._categories:
+            msg = f"Already have a category named '{name}'"
+            raise KeyError(msg)
+        self._categories[name] = cat_type()
diff --git a/estimage/solutions/__init__.py b/estimage/solutions/__init__.py
index fd12f56..262fadf 100644
--- a/estimage/solutions/__init__.py
+++ b/estimage/solutions/__init__.py
@@ -21,14 +21,17 @@ def prime(self, cards: typing.Iterable[BaseCard]):
 
 class SolutionByUpdating(Solution):
     end_value: float
+    updates_model: bool
 
     def __init__(self):
         super().__init__()
         self.end_value = None
+        self.updates_model = True
 
     def describe(self):
         return f"Update the record of '{self.card_name}'"
 
+
 class SolutionByUpdatingChildren(SolutionByUpdating):
     action = "update_children_points"
 
@@ -46,6 +49,7 @@ class SolutionByUpdatingSelf(SolutionByUpdating):
 
     def __init__(self):
         super().__init__()
+        self.updates_model = False
 
     def describe(self):
         return f"Update the record of '{self.card_name}', so it matches records of its children."
@@ -54,6 +58,11 @@ def prime(self, cards: typing.Iterable[BaseCard]):
         pass
 
 
+class SafeSolutionByUpdatingSelf(SolutionByUpdatingSelf):
+    def describe(self):
+        return f"Update the record of '{self.card_name}', so it matches records of its children, likely reflecting their development."
+
+
 class ProblemSolver:
     SOLUTIONS = []
 
@@ -77,6 +86,21 @@ def problem_solution(func):
     return func
 
 
+@problem_solution
+def get_safe_solution_of_inconsistent_parent(problem: Problem):
+    if "inconsistent_estimate" not in problem.tags:
+        return
+    if "estimate_within_nominal" not in problem.tags:
+        return
+    if "sum_of_children_lower" not in problem.tags:
+        return
+    if "missing_estimates" in problem.tags:
+        return
+    ret = SafeSolutionByUpdatingSelf()
+    ret.card_name = problem.affected_card_name
+    return ret
+
+
 @problem_solution
 def get_solution_of_inconsistent_parent(problem: Problem):
     if "inconsistent_estimate" not in problem.tags:
@@ -84,7 +108,7 @@ def get_solution_of_inconsistent_parent(problem: Problem):
     if "missing_estimates" in problem.tags:
         return
     ret = SolutionByUpdatingSelf()
-    ret.card_name = problem.affected_cards_names[0]
+    ret.card_name = problem.affected_card_name
     return ret
 
 
@@ -98,5 +122,5 @@ def get_solution_of_inconsistent_children(problem: Problem):
         return
 
     ret = SolutionByUpdatingChildren()
-    ret.card_name = problem.affected_cards_names[0]
+    ret.card_name = problem.affected_card_name
     return ret
diff --git a/estimage/webapp/main/forms.py b/estimage/webapp/main/forms.py
index e8118e8..e2d5035 100644
--- a/estimage/webapp/main/forms.py
+++ b/estimage/webapp/main/forms.py
@@ -98,3 +98,31 @@ class PointEstimationForm(FlaskForm):
     most_likely = wtforms.SelectField("Most Likely", choices=FIB)
     pessimistic = wtforms.SelectField("Pessimistic", choices=FIB)
     submit = SubmitField("Save Estimate")
+
+
+class MultiCheckboxField(wtforms.SelectMultipleField):
+    """
+    A multiple-select, except displays a list of checkboxes.
+
+    Iterating the field will produce subfields, allowing custom rendering of
+    the enclosed checkbox fields.
+    """
+    widget = wtforms.widgets.ListWidget(prefix_label=False)
+    option_widget = wtforms.widgets.CheckboxInput()
+
+    def get_selected(self):
+        ret = []
+        for x in self:
+            print(11, x, 22)
+
+
+class ProblemForm(FlaskForm):
+
+    def add_problems(self, problems):
+        for p in problems:
+            self.problems.choices.append((p.affected_card_name, p.description))
+
+    problem = wtforms.HiddenField("problem")
+    solution = wtforms.HiddenField("solution")
+    problems = MultiCheckboxField("Problems", choices=[])
+    submit = SubmitField("Solve Problems")
diff --git a/estimage/webapp/main/routes.py b/estimage/webapp/main/routes.py
index 16051fb..d1bdee9 100644
--- a/estimage/webapp/main/routes.py
+++ b/estimage/webapp/main/routes.py
@@ -447,6 +447,33 @@ def view_problems():
     solver = solutions.ProblemSolver()
     sols = {p.description: solver.get_solution_of(p) for p in probs}
 
+    form = forms.ProblemForm()
+    form.add_problems(problem_detector.problems)
+    form.problem.data = "Missing Update"
+    form.solution.data = "Update parents"
+
     return web_utils.render_template(
         'problems.html', title='Problems',
-        all_cards_by_id=all_cards_by_id, problems=probs, solutions=sols)
+        all_cards_by_id=all_cards_by_id, problems=probs, solutions=sols, form=form)
+
+
+@bp.route('/problems/fix', methods=['POST'])
+@flask_login.login_required
+def fix_problems():
+    user = flask_login.current_user
+    user_id = user.get_id()
+
+    all_cards_by_id, model = web_utils.get_all_tasks_by_id_and_user_model("retro", user_id)
+    all_cards = list(all_cards_by_id.values())
+
+    problem_detector = problems.ProblemDetector(model, all_cards)
+
+    form = forms.ProblemForm()
+    form.add_problems(problem_detector.problems)
+    if form.validate_on_submit():
+        print(f"Fix {form.problem.data} by {form.solution.data}")
+        print(f"Fix: {form.problems.data}")
+    else:
+        flask.flash(f"Error handing over solution: {form.errors}")
+    return flask.redirect(
+        web_utils.head_url_for("main.view_problems"))
diff --git a/estimage/webapp/templates/problems.html b/estimage/webapp/templates/problems.html
index 737300f..c09fca9 100644
--- a/estimage/webapp/templates/problems.html
+++ b/estimage/webapp/templates/problems.html
@@ -1,14 +1,11 @@
 {% extends "general_retro.html" %}
 
 {% import "utils.j2" as utils with context %}
+{% from 'bootstrap5/form.html' import render_form %}
 
 
-{% macro print_name_replaced_with_links(text, names) %}
-{% if names | length > 1 %}
-{{ print_name_replaced_with_links(print_name_replaced_with_links(text, [names[0]]), names[1:]) }}
-{% else %}
-{{ text.replace(names[0], utils.task_or_epic_link(all_cards_by_id[names[0]], "retrospective")) | safe }}
-{% endif %}
+{% macro print_name_replaced_with_links(text, name) %}
+{{ text.replace(name, utils.task_or_epic_link(all_cards_by_id[name], "retrospective")) | safe }}
 {% endmacro %}
 
 
@@ -18,9 +15,9 @@ <h2>Problems</h2>
     <div class="row">
     <div>
     {% for p in problems %}
-    <h3>{{ " ".join(p.affected_cards_names) }}</h3>
+    <h3>{{ p.affected_card_name }}</h3>
     	<p>
-        {{ print_name_replaced_with_links(p.description, p.affected_cards_names) }}
+        {{ print_name_replaced_with_links(p.description, p.affected_card_name) }}
     	</p>
     	<p>
 	Tags:
@@ -34,6 +31,13 @@ <h3>{{ " ".join(p.affected_cards_names) }}</h3>
     	</p>
     {% endfor %}
     </div>
+    <div>
+    <h3>Inconsistent Values of Parents</h3>
+    	<p>
+	Solvable by updating parents to match children.
+    	</p>
+        {{ render_form(form, action=head_url_for("main.fix_problems")) }}
+    </div>
     </div>
 </div>
 {% endblock content %}
diff --git a/tests/test_problems.py b/tests/test_problems.py
index 3a29b97..b714631 100644
--- a/tests/test_problems.py
+++ b/tests/test_problems.py
@@ -66,12 +66,22 @@ def test_model_notices_basic_inconsistency(cards_one_two):
     assert "of 1" in problem.description
 
 
-def test_model_notices_inconsistency_maybe_caused_by_progress(cards_one_two):
+def test_model_notices_inconsistency_unlikely_caused_by_progress(cards_one_two):
     card_one, card_two = cards_one_two
     card_two.point_cost = 0.5
     problem = get_problem_of_cards(cards_one_two)
     assert "inconsistent_estimate" in problem.tags
     assert "sum_of_children_lower" in problem.tags
+    assert not "estimate_within_nominal" in problem.tags
+
+
+def test_model_notices_inconsistency_probably_caused_by_progress(cards_one_two):
+    card_one, card_two = cards_one_two
+    card_two.status = "done"
+    problem = get_problem_of_cards(cards_one_two)
+    assert "inconsistent_estimate" in problem.tags
+    assert "sum_of_children_lower" in problem.tags
+    assert "estimate_within_nominal" in problem.tags
 
 
 def test_model_notices_children_not_estimated(cards_one_two):
@@ -99,4 +109,54 @@ def test_model_finds_status_problem(cards_one_two):
 
     card_two.point_cost = card_one.point_cost
     problem = get_problem_of_cards(cards_one_two)
-    assert "one" in problem.affected_cards_names
+    assert "one" == problem.affected_card_name
+
+
+def test_problem_categories_trivial():
+    dumb_classifier = tm.ProblemClassifier()
+    p = tm.Problem()
+    p.add_tag("urgent")
+    dumb_classifier.classify([p])
+    others = dumb_classifier.not_classified
+    assert len(others) == 1
+    assert others[0] == p
+
+
+class CustomClassifier(tm.ProblemClassifier):
+    pass
+
+
+class Underestimation(tm.ProblemCategory):
+    name = "underestimation"
+
+    def matches(self, p):
+        return "underestimated" in p.tags
+
+
+def test_problem_category_match():
+    cat = Underestimation()
+    p = tm.Problem()
+    p.add_tag("underestimated")
+    assert cat.matches(p)
+
+    bad_p = tm.Problem()
+    bad_p.add_tag("nothing")
+    assert not cat.matches(bad_p)
+
+
+def test_problem_categories_no_duplication():
+    smart_classifier = CustomClassifier()
+    smart_classifier.add_category_type(Underestimation)
+    with pytest.raises(KeyError):
+        smart_classifier.add_category_type(Underestimation)
+
+
+def test_problem_categories_basic():
+    smart_classifier = CustomClassifier()
+    smart_classifier.add_category_type(Underestimation)
+    p = tm.Problem()
+    p.add_tag("underestimated")
+    smart_classifier.classify([p])
+    assert not smart_classifier.not_classified
+    urgent_problems = smart_classifier.classified_problems
+    assert urgent_problems["underestimation"][0] == p
diff --git a/tests/test_solutions.py b/tests/test_solutions.py
index 71d127b..1c0bfc4 100644
--- a/tests/test_solutions.py
+++ b/tests/test_solutions.py
@@ -26,6 +26,7 @@ def test_basic_inconsistency_solution(solver, cards_one_two):
     solution = solutions[0]
     assert solution.action == "update_points"
     assert solution.card_name == "one"
+    assert solution.updates_model == False
     solution.prime([card_one])
     # assert solution.end_value == card_two.point_cost
 
@@ -42,6 +43,7 @@ def test_update_children_inconsistency_solution(solver, cards_one_two):
     solution = solutions[0]
     assert solution.action == "update_children_points"
     assert solution.card_name == "one"
+    assert solution.updates_model == True
     solution.prime([card_one])
     assert solution.end_value == card_one.point_cost / 2.0