I had a very similar experience regarding Jifty's user permission built-ins (and the docs which ostensibly describe them). Really, the whole project was a sequence of:

• Try to find FEATURE_X in the docs. On failure, skip next step.
• Try to extrapolate proper usage of FEATURE_X in REAL_LIFE_SITUATION_Y from the single provided line of sample code.
• Beat head against wall for several hours.
• Bug Jesse Vincent on IRC. Jesse provides the Right Way to do it in about ten seconds and 35 characters.
• Code it. The solution generally works and is elegant.
• 20 GOTO 10

I can easily imagine how keeping Mason and throwing the rest out could make your life a lot more pleasant, especially if you don't need AJAX/continuations/insulation from SQL/a pony/other features that Jifty provides out of the box.