Ok guys, here is the deal.
I'm actually blind, I.E cannot see.
So,When the smell of food is in the air, I don't put my hands in the tub at all. lol
That is why I was trying to figure out the best way to feed.
So, it looks like I'll feed the ball on Thursdays, and just won't go in the boa tub that night either. Then When the boa gets fed, the same for the ball.

You say prescenting isn't needed for boa's, but would it help keep them out of the habit of expecting food everytime the lid comes off?
That's why I mainly prescent for the ball.
Again, it's more of a safety thing sense I'm blind and am just sticking my hand in the tub on faith their not hungry. lol
It's not because I just want to hold all the time.

Hope this makes more sense.

Now on the Shed, I guess it won't hurt them to eat if they are in shed?
Is there any other way to know if they are getting ready to shed other than colors?
My ball will act a little different while being held.
She won't really uncurl, and stays a little tense, and gets a little jumpy. Then the big one, she refuses food, which so far she only does during the actual shed.

Any traits like that to help me out?

About how long does a boa's shed process last?

Sorry for the explanations, but it might help you guys see where I'm coming from.