i might sing along. having to create 100+-pages magazines. yes, 7.31 is very slow on G5-MPs. the fastest ever G5 (2*2,7) is blowing like a boeing or an airbus on take-off. i have to admit that a G5DC (last series ever) with 2,3 dual core is faster - and was much more cheaper :-( than the first one mentioned. both running with 8GB RAM. whereas an intel macbookpro is quite fast (but to date not really as 6.52 used to be).
things which did speed up a bit (but do not transform a G5 to a MacPro):
* cleaning font cache daily
* not too often run apple-f (search and find) this always brings up display problems after some time.
* move dejavu XT from xtensions to xtensions disabled (this speeds up the save process)
* from time to time create new preferce file (yes, this will force one to create all settings and S&B (in german) again) and never share the preference file between a G5MP, G5DC or intel mac (might be an easy way to get settings from one to another).
* plsu all other standard things as checked fonts, pictures and full res preview only when needed, correctly upgraded older files to 7 etc etc.