sympy/sympy — pull request #1074 by smichr (2012-02-21 19:11:20+00:00)
Title: 3024: try powsimp with a Mul rather than an Add

While looking this over, I noticed that the measure keyword
was not being passed along, so that was modified in powsimp.

The modification here was made because Add factors of a Mul
are treated differently than an Add in powsimp, and sometimes
(not always) the factor-treatment leads to a simpler expression.
This tries to fail as soon as possible: if the powsimp results
are not different then the procedure reverts back to what it
was before this commit.

http://code.google.com/p/sympy/issues/detail?id=3024