diff --git a/scalding-core/src/test/scala/com/twitter/scalding/typed/OptimizationRulesTest.scala b/scalding-core/src/test/scala/com/twitter/scalding/typed/OptimizationRulesTest.scala
index 74fdcb8a05..58f1492771 100644
--- a/scalding-core/src/test/scala/com/twitter/scalding/typed/OptimizationRulesTest.scala
+++ b/scalding-core/src/test/scala/com/twitter/scalding/typed/OptimizationRulesTest.scala
@@ -21,29 +21,36 @@ object TypedPipeGen {
   }
 
   def mapped(srcGen: Gen[TypedPipe[Int]]): Gen[TypedPipe[Int]] = {
+    val commonFreq = 10
     val next1: Gen[TypedPipe[Int] => TypedPipe[Int]] =
-      Gen.oneOf(
-        tpGen(srcGen).map { p: TypedPipe[Int] =>
+      Gen.frequency(
+        (1, tpGen(srcGen).map { p: TypedPipe[Int] =>
           { x: TypedPipe[Int] => x.cross(p).keys }
-        },
-        tpGen(srcGen).map { p: TypedPipe[Int] =>
+        }),
+        (2, tpGen(srcGen).map { p: TypedPipe[Int] =>
           { x: TypedPipe[Int] => x.cross(ValuePipe(2)).values }
-        },
+        }),
         //Gen.const({ t: TypedPipe[Int] => t.debug }), debug spews a lot to the terminal
-        Arbitrary.arbitrary[Int => Boolean].map { fn =>
+        (commonFreq, Arbitrary.arbitrary[Int => Boolean].map { fn =>
           { t: TypedPipe[Int] => t.filter(fn) }
-        },
-        Gen.const({ t: TypedPipe[Int] => t.forceToDisk }),
-        Gen.const({ t: TypedPipe[Int] => t.fork }),
-        tpGen(srcGen).map { p: TypedPipe[Int] =>
+        }),
+        (commonFreq, Arbitrary.arbitrary[Int => Int].map { fn =>
+          { t: TypedPipe[Int] => t.map(fn) }
+        }),
+        (commonFreq, Arbitrary.arbitrary[Int => List[Int]].map { fn =>
+          { t: TypedPipe[Int] => t.flatMap(fn.andThen(_.take(4))) } // the take is to not get too big
+        }),
+        (2, Gen.const({ t: TypedPipe[Int] => t.forceToDisk })),
+        (2, Gen.const({ t: TypedPipe[Int] => t.fork })),
+        (5, tpGen(srcGen).map { p: TypedPipe[Int] =>
           { x: TypedPipe[Int] => x ++ p }
-        },
-        Gen.identifier.map { id =>
+        }),
+        (1, Gen.identifier.map { id =>
           { t: TypedPipe[Int] => t.addTrap(TypedText.tsv[Int](id)) }
-        },
-        Gen.identifier.map { id =>
+        }),
+        (1, Gen.identifier.map { id =>
           { t: TypedPipe[Int] => t.withDescription(id) }
-        })
+        }))
 
     val one = for {
       n <- next1
@@ -73,7 +80,8 @@ object TypedPipeGen {
       for {
         single <- tpGen(srcGen)
         fn <- Arbitrary.arbitrary[Int => List[(Int, Int)]]
-      } yield single.flatMap(fn))
+      } yield single.flatMap(fn.andThen(_.take(4))) // take to not get too big
+      )
 
     val two = Gen.oneOf(
       for {
@@ -83,7 +91,7 @@ object TypedPipeGen {
       for {
         fn <- Arbitrary.arbitrary[Int => List[Int]]
         pair <- keyRec
-      } yield pair.flatMapValues(fn),
+      } yield pair.flatMapValues(fn.andThen(_.take(4))), // take to not get too big
       for {
         fn <- Arbitrary.arbitrary[Int => Int]
         pair <- keyRec
@@ -106,7 +114,7 @@ object TypedPipeGen {
       for {
         p1 <- keyRec
         p2 <- keyRec
-      } yield p1.hashJoin(p2).values,
+      } yield p1.hashJoin(p2).mapValues { case (a, b) => 31 * a + b },
       for {
         p1 <- keyRec
         p2 <- keyRec
@@ -114,7 +122,7 @@ object TypedPipeGen {
       for {
         p1 <- keyRec
         p2 <- keyRec
-      } yield p1.join(p2).mapValues { case (a, b) => a * b }.toTypedPipe)
+      } yield p1.join(p2).mapValues { case (a, b) => a + 31 * b }.toTypedPipe)
 
     // bias to consuming Int, since the we can stack overflow with the (Int, Int)
     // cases