The way I was shown force feeding of a hatchling was:
- Dunk the defrosted pink's head in some sort of water-based lubricant e.g. KY jelly (NOT Vaseline which is petroleum-based). I also used the vegetable oil from a tin of tuna.
- Holding the hatchling still (good luck with that...), gently prise it's mouth slightly open with something flat and blunt, like the edge of a credit card.
- When you have its mouth open far enough to take the head of the pink, put the pink in the mouth and VERY gently push it into the throat.
- When the pink is far enough in the hatchling's throat, start VERY GENTLY massaging it, so that it gradually works its way down the body. It's at the stomach when it's about a third of the way down to the cloaca.
Needless to say, there's the potential to hurt the hatchling at every stage of this process, so it's really best if you can get an experienced keeper to show you. It's also easier to accomplish if there are two of you to do the feeding. Do expect to end up with burst pinks, mouse guts all over you, and a very stressy, slippery snake.
As far as benefits are concerned, I did it with persistent non-feeders for two seasons, and I never had one of them survive. They always kept the pinks down and seemed to poop normally as a result of eating, but they never thrived and all of them died in the end, after months of trying.
I'm afraid I tend toward the view that if a hatchling doesn't eat of its own accord with all of the usual tricks (braining, slitting, scenting, leaving overnight etc), then there's probably something fundamentally wrong with it anyway. Not to mention the fact that the process can be very stressful for the hatchling, which is never helpful in a survival situation.
I don't force-feed any more.
I've never tube-fed, so can't comment on that.