I know this is probably going against the grain here, but I've always fed my chams larger prey than the between the eyes rule. I fed my last veiled supers at 4 months. Theres no one to regulate them in the wild. I've never had one come close to choking.
Ahhh, but these animals are in captivity and we have the ability/responsibility to feed them appropriate sized prey.
The distance between the eyes rule is probably an overly safe one ... most bugs crunch up pretty easily, but it's certainly not a bad idea to give them (maybe a few more) a size of prey that is easily manageable.
The range of sizes of 5 month old veileds is surprisingly large. Therefore (in my opinion) it is not enough to just know the age of the animal. How big is it? Snout to vent?
Brads right about the size and not the age. The four month old I was talking about was very large for his age. Probably close to 4" nose to vent and very robust. I'm not reckless with the size that I give them but don't hold to the between the eyes rule. My 4 month old had no problems whatsoever handling the superworms.