I dont go by the rule of 3... i have found over years of breeding that corns will breed when ready.
I dont for one minute believe that they can rape each other, so if the female isn big enough,she simply wont breed..
I have had one eggbound, a 600 gram female.. for me this is too big, i like mine to be more slender, around 400 grams but will go down to 250 if the underbelly is strong enough..
Have a nice amount of egg in the incubator, so hoping for some real stunning stuff this year.