Safe handling practice for large snakes

[DrSimonsSays]

My hubby and I have an 11 foot or so beautiful Burmese morph sold as a "jigsaw". He is close to 40 lbs. We have him out of the cage in our bedroom for much of the day, and we are both in contact with him at least 4-6 hours every day. I'm pretty sure he thinks he is human. Definitely the 2 person rule, but only when he is on the floor in front of his cage--as that is where we always feed him (on a towel).
Ours is about 95% potty trained. He has only gone in his cage when left in there while we were on a vacation.
When he needs to go, he pushes the door to our bathroom area open and crawls into the spa tub. We fill it with water, and watch his tail. Once it starts to flatten out and go up, I grab the butt and hold it over a large cup (he doesn't like ANY urine or feces in his bath water, he'll jump outta fast as an 11ft snake can) then he just goes in the cup. Sometimes I help express out the pellets by massaging his underbelly. Then LOTS of positive reinforcement, of course. If he hasn't urinated for a week, we'll put him in the tub, and he knows what we expect of him. After one "accident" on our Tempurpedic, that is all we wanted.
I'm thinking that potty training might only be possible on bigger snakes that are VERY well socialized; regardless, we are very happy to have a OCD clean snake!