There are no short cuts to picking ball moss (Tillandsia recurvata). Sometimes it comes off easily, but inevitably some of it grabs on so well you practically have to tear off the branch to get it loose. Many times, I've done 99% of a branch in a few minutes, then fought with the last ball for several more (sometimes finally pulling it off, other times finally breaking the *%%$#@ branch and having to remove it). In the end, you'll do best to get your hand on every piece possible and save the pole saw for the tips.
I've seen a lot of attempts to modify saws for picking, from filing notches in the tip and back of the blade, to adding a separate hook made from an old blade, to removing the blade and putting a fork on the pole head. I don't think any of it really helps a lot, but whatever you choose, you get better with practice.
Spraying, then scraping may be your best bet if you don't need perfect-looking results. Once the moss is dried out, it should come off much more easily, if less completely. As Oakwilt said, baking soda works, though it is not labeled for the purpose so not technically legal for you to use it. Kocide is approved, though guys I know with sprayers don't like what that does to their equipment.
In the end, getting your hands on the stuff and tearing it apart is the only sure way to really get it out of there completely. If you start selling these jobs, bid high.
good luck,
k
