diff --git a/data/ai/micro_ais/micro_ai_unit_variables.lua b/data/ai/micro_ais/micro_ai_unit_variables.lua
index 583b20c6bcdf..0892a4d9f4c1 100644
--- a/data/ai/micro_ais/micro_ai_unit_variables.lua
+++ b/data/ai/micro_ais/micro_ai_unit_variables.lua
@@ -1,86 +1,50 @@
 -- This set of functions provides a consistent way of storing Micro AI
--- variables in units. They need to be stored inside a [micro_ai] tag in a
--- unit's [variables] tag together with an ai_id= key, so that they can be
--- removed when the Micro AI gets deleted. Otherwise subsequent Micro AIs used
--- in the same scenario (or using the same units in later scenarios) might work
--- incorrectly or not at all.
--- Note that, with this method, there can only ever be one of these tags for each
--- ai_ca in each unit (but of course several when there are several Micro AIs
--- with different ai_CA values affecting the same unit)
--- For the time being, we only allow key=value style variables.
+-- variables in units. Individual variables are stored inside a table with a
+-- name specific to the MAI ('micro_ai-' .. ai_id). This table is removed when
+-- the Micro AI is deleted in order to ensure that subsequent Micro AIs used
+-- in the same scenario (or using the same units in later scenarios) work
+-- correctly.
+-- Note that, with this method, there can only ever be one of these tables for each
+-- ai_id in each unit, but several tables are created for the same unit when there
+-- are several Micro AIs with different ai_id values.
+-- For the time being, we do not allow sub-tables. This is done because these
+-- unit variables are required to be persistent across save-load cycles and
+-- therefore need to be in WML table format. This could be extended to allow
+-- sub-tables in WML format, but there is no need for that at this time.
 
 local micro_ai_unit_variables = {}
 
-function micro_ai_unit_variables.modify_mai_unit_variables(unit, ai_id, action, vars_table)
-    -- Modify [unit][variables][micro_ai] tags
-    -- @ai_id (string): the id of the Micro AI
-    -- @action (string): "delete", "set" or "insert"
-    -- @vars_table: table of key=value pairs with the variables to be set or inserted (not needed for @action="delete")
-
-    local variables = unit.variables.__cfg
-
-    -- Always delete the respective [variables][micro_ai] tag, if it exists
-    local existing_table
-    for i,mai in ipairs(variables) do
-        if (mai[1] == "micro_ai") and (mai[2].ai_id == ai_id) then
-            existing_table = mai[2]
-            table.remove(variables, i)
-            break
-        end
-    end
-
-    -- Then replace it, if the "set" action is selected
-    -- or add the new keys to it, overwriting old ones with the same name, if action == "insert"
-    if (action == "set") or (action == "insert") then
-        local tag = { "micro_ai" }
-
-        if (not existing_table) or (action == "set") then
-            tag[2] = vars_table
-            tag[2].ai_id = ai_id
-        else
-            for k,v in pairs(vars_table) do existing_table[k] = v end
-            tag[2] = existing_table
-        end
-
-        table.insert(variables, tag)
-    end
-
-    -- All of this so far was only on the table dump -> apply to unit
-    unit.variables.__cfg = variables
-end
-
 function micro_ai_unit_variables.delete_mai_unit_variables(unit, ai_id)
-   micro_ai_unit_variables.modify_mai_unit_variables(unit, ai_id, "delete")
+    unit.variables['micro_ai_' .. ai_id] = nil
 end
 
 function micro_ai_unit_variables.insert_mai_unit_variables(unit, ai_id, vars_table)
-   micro_ai_unit_variables.modify_mai_unit_variables(unit, ai_id, "insert", vars_table)
+    local mai_var = unit.variables['micro_ai_' .. ai_id] or {}
+    -- Restrict to top-level named fields
+    for k,v in pairs(vars_table) do mai_var[k] = v end
+    unit.variables['micro_ai_' .. ai_id] = mai_var
 end
 
 function micro_ai_unit_variables.set_mai_unit_variables(unit, ai_id, vars_table)
-    micro_ai_unit_variables.modify_mai_unit_variables(unit, ai_id, "set", vars_table)
+    local mai_var = {}
+    -- Restrict to top-level named fields
+    for k,v in pairs(vars_table) do mai_var[k] = v end
+    unit.variables['micro_ai_' .. ai_id] = mai_var
 end
 
 function micro_ai_unit_variables.get_mai_unit_variables(unit, ai_id, key)
-    -- Get the content of [unit][variables][micro_ai] tag for the given @ai_id
+    -- Get the content of [unit][variables]['micro_ai_' .. ai_id] tag
     -- Return value:
-    --   - If tag is found: value of key if @key parameter is given, otherwise
-    --     table of key=value pairs (including the ai_id key)
-    --   - If no such tag is found: nil (if @key is set), otherwise empty table
+    --   - If tag is found: value of key if @key parameter is given, otherwise entire table
+    --   - If no such tag is found: nil if @key is given, otherwise empty table
 
-    for mai in wml.child_range(unit.variables.__cfg, "micro_ai") do
-        if (mai.ai_id == ai_id) then
-            if key then
-                return mai[key]
-            else
-                return mai
-            end
-        end
-    end
+    local mai_var = unit.variables['micro_ai_' .. ai_id] or {}
 
-    -- If we got here, no corresponding tag was found
-    -- Return empty table; or nil if @key was set
-    if (not key) then return {} end
+    if key then
+        return mai_var[key]
+    else
+        return mai_var
+    end
 end
 
 return micro_ai_unit_variables