Repeatedly applying trigsimp, ratsimp etc.

Hello,

Maxima has a lot of different simplification functions.
I'm looking for a way to "try them all" and find the simplest expression.
Basically I want to do this:

Given an expression e, compute trigsimp(e), ratsimp(e), radcan(e) ...
See which of these gives the "simplest" result and do the same again 
with this simpler result.
Stop when none of the functions can produce a simpler result any more.

First I thought that "scsimp" was the right function to do this, and I 
tried it like this:

matchdeclare(x, true);
defrule(r1, x, trigsimp(x));
defrule(r2, x, ratsimp(x));
// more rules follow

// my expression to be simplified
// it equals to 1, if you apply "trigsimp"
expr : tan(x) * cot(x)

scsimp(expr, r1, r2, ...);

However, "scsimp" doesn't apply any of the rules.
If I manually apply rule "r1", it gives me the correct result "1".

Am I doing something wrong? Or does "scsimp" just not work like this?
How could I do it manually? Is there a Maxima function that computes the 
length of an expression, so I could use it to select the best result in 
each step?

I'm very grateful for any help.

Kind regards,
David Scherfgen