How valuable is raising your proficiency beyond 100? Is is better than a certain amount of hitroll if it is your weapon skill? Is it just an effective "+1" to those contested dice rolls?
Proficiency above 100
Depends heavily on which skill or spell we are talking about. It is never bad to have over 100 but in some cases it makes a HUGE difference.
In weapons cases you do more damage or defend and attack more often. If it's a main skill you use a lot it would also make a huge difference.
I.E. Disarm for exotic warrior
Weaponcleave for zerks
Backstab for a thief holy cow!
I'd take those over a few hitroll any day.
In skills like crafting it could mean you create things you could not at 100%. May also affect chances of managing to retain materials when dismantling as a bard.
In the case of defenses it is IMO almost a must In the current environment for races that can not reach the -600AC mark.
In the end, a famous Rabi once said, reading the Torah 100 times can in no way be compared to reading it 101 times. :)
Edit: Welcome home by the way.
Edited
Kinda repeat from the other thread, but having 100+ protects from fear/hysteria proficiency drops. That can be huge against a few higher ranked cabal and other qrace/shaman fights.