I've got a male who is 4 to 5 years old and he seriously only eats 3 to 5 meals per year. He's in perfect health, breeds like mad, and has good body mass and muscle tone. He hasn't eaten since last september or october. He wants nothing to do with food during the breeding season, and he wishes the breeding season would last year round. He'll proably take a rat in the next few weeks, then a few more over the next couple of months, then quit again.
The thing is, I don't see it as a problem. People write in all the time freaked out by a 6 week fast....I've never had a BP starve themselves to death, and I challenge anyone out their to point out a case where one has. I've rehabilitated a couple of WC adults, non feeding babies, etc, and they all eat at some point. People are so used to cramming their pie hole 3 (or more) times a day, we often just aren't comfortable with animals that don't need to do that.
As far as the babies eating great then stopping, I haven't had a lot of that. My animals usually dont go off feed until breeding time, and I have a few that I think would feed throughout. I don't even offer food to adults from late novemeber though January. I think the key may be in power feeding. My babies never get power fed. My guess is that the ones who eat every 3-5 days, and eat multiple prey items per feeding put on too much weight too quickly, and basically put themselves on a diet.