Simplifier loop through cast worker/wrapper

With HEAD, if you try to compile typecheck/should_compile/T11754, with -fmax-simplifer-iterations=8 you'll see that the simplifier just iterates:

==================== Simplifier iteration=2 ====================
  ---- Simplifier counts for Simplifier iteration=2
  Total ticks:     8
  
  8 UnfoldingDone
    4 $cp1Differentiable_aGz
    4 $cp1Differentiable_aGK
  1 SimplifierDone 1

...

==================== Simplifier iteration=3 ====================
  ---- Simplifier counts for Simplifier iteration=3
  Total ticks:     8
  
  8 UnfoldingDone
    4 $cp1Differentiable_sJZ
    4 $cp1Differentiable_sK0
  1 SimplifierDone 1

And so on indefinitely. The problem is that we have this

Rec { bar1 = /\ a b. \d1 d2. bar a b e1 e2
    ; bar = bar1 |> co }

The occurrence analyser picks bar1 as the loop breaker, so we inline bar into bar1 to get

Rec { bar1 = /\ a b. \d1 d2. (bar1 |> co) a b e1 e2 }

Then we push that cast to the right, in fact outside the entire lambda, to get

Rec { bar1 = (/\ a b. \d1 d2. bar1 a b e1 e2) |> co }

and then we do cast worker/wrapper to get

Rec { bar2 = /\ a b. \d1 d2. bar1 a b e1 e2
    ; bar1 = bar1 |> co }

and we are back to where we started.

Cure

I think we still want to do cast w/w for recursive functions. What's odd this one is bottom. So maybe disable cast w/w for bottoming functions?