Cant answer the 5x leveling, but will answer the weapon skill question. You are always assumed to have max weapon skill in bear form, yes. Feral forms do NOT take weapon damage into consideration. At some point you will get to weapons (i think they might have only made the change for level 60+ weapons but im not sure, ive been max level for too long) that have a stat called feral Attack power on them, which is based on the weapon damage. Until you see that, weapons are just stat sticks for you and you are compensated by stats inherent to the forms themselves.

Hope thats helpful.

edit: If you browse http://www.wowhead.com/?items=2.5#0-3+1 youll notice that all TBC and WOTLK 2h maces have feral attack power shown. Some of the level 60 stuff does too but some of it doesnt so at some point they start giving you that stat, dont know what the cut off is exactly.