Man...go away for a few months and look what happens.
So standard disclaimers apply. I haven't breed my snakes, but I've breed lots of other things so I've had to make some tough choices on how far could I reasonably take things before saying enough is enough and doing what is right. That said.
I've dealt with several non/fussy eaters. 2 didn't make it. 1 (corn) died shortly after hatching, the 2nd (cal king) was a sporadic eater that once in a while would only take live, but would occasionally take a f/t, sometimes would refuse for weeks on end. After 6-8 months of stress for both of us he died. I have a 3rd that as a baby wouldn't touch a mouse if he was about to shed/was shedding/just shed. He's mostly outgrown it. If he doesn't eat that time, he gets to wait until his next feeding. Period.
I've tried tease feeding. All it seems to do is stress them out and make it harder to feed them next time. Same with force feeding. I would only consider tube feeding on an established snake that had some sort of illness that was temporary.
Food preference is partially genetic. It's part of the selection process. Those that prefer a given food source that is abundant in one area will not do as well if taken out of that environment and given something else. Some may adapt, others will die. The one's who adapt will produce babies that are more likely to choose the more abundant food source. We are breeding animals in a artificial environment. We can select for animals that do better in that environment. Corns have been breed in captivity for decades and as a result of that selection now have the reputation of being easy to care for eating machines.
So to sum up. I will offer f/t, live, leave them overnight, wash/brain/some scenting (I draw the line at lizard scenting. I see no reason to do in the lizard for this). No force feeding or tube feeding.
Breeding should be taken on with a goal in mind, not just because you have two animals of the appropriate gender. If you can't add/improve something to the breed. Don't do it. Breeding is a serious responsibility and should be treated as such.
Hmmm...I appear to have found a soap box. I think I'll get off it now, I'm afraid of heights.
Oh yeah, my snakes are living, breathing creatures with individual personalities. I've also seen deeper puddles.
Shannon