One thing I did notice with a high level monk is the following is possible
Imagine a level 10 monk with 30 ranks in Acrobatics, Dual Sai, Martial arts strikes, sweeps, Weapon Sai and Chi Defense. Let's say the stat bonus for each is 20. He has a +20 Sai, two of them and has acquired the Bracers of Armor with a +60DB.
The Dual Sai OB would be 50+20+10+20+10 for specialization and you have a 110OB. Add a +20 Sai and that becomes a 130OB. Not bad, but let look at the DB.
Let's say 20 in the quickness bonus + 90 in Chi Defense (80+10) + 60 with the bracers plus +30 if I use Dual Sai for a grand total of 200DB! :O Holy cow!
A 130OB and a 200DB? (And according to certain rulings that DB applies to all attacks. :O