I am not aware of any arrow restrictions for Pope & Young, the let off is as stated no more than 65%. However you can enter a deer shot with a bow in Boone & Crockett and the let off does not matter, meaning above 65% is aok as long as you meet the min. score.
P & Y Scores for deer are:
Mule Typical: 145
Mule Nontypical: 170
WT Typical: 125
WT Nontypical: 155
B & C have two catagories they acknowledge - Awards and All-time (Book)
Awards:
Mule Typical: 180
Mule Non Typical: 215
WT Typical: 160
WT Nontypical: 185
All-Time:
Mule Typical: 190
Mule Non-Typical: 230
WT Typical: 170
WT NonTypical: 195
Any other rules, scoring information, etc can be found on their websites:
www.pope-young.org
www.boone-crockett.org