Sorry, but it appears there's some misinformation here.
You shouldn't feed your snake twice a week (meaning 7 days, making your regiment every 3-4 days?). It's too much, and doesn't give them a chance to digest and defecate before you put more food into their system. At the most, you should feed every 5-7 days. Every 5-7 days works fine for hatchlings who are eating pinkies. When they get big enough for fuzzies, you should move to every 7 days... And so on, until they reach adulthood, when they should be taking one adult mouse every 10-14 days.
My favorite
guideline (it's just a guideline, not a strict regiment by any means) for corn feeding is the "Munson Plan." Here it is--direct copy and paste from the original thread on the CornSnakes.Com forum:
"The Munson Plan (Sample Feeding Chart)
-When they're on single pinks (2-3g), I feed every 5-6 days. (Snake = 4-15g)
-Double pinks (3g x 2) every 5-6 days. (Snake = 16-23g)
-Small fuzzies (5-7g) every 6-7 days. (Snake = 24-30g)
-Regular fuzzies (7-9g) every 6-7 days (Snake = 30-50g)
-Hoppers (9-12g) every 6-7 days (Snake = 51-90g)
-Weaned (14-20g) every 7 days (Snake = 91-170g)
-Adult (20-30g) every 7-x days (Snake = 170+) See below.
Note: Adult females are fed more frequently than adult males (especially following brumation). Adult females are fed every 7-12 days; adult males are fed every 11-14 days.
This is by no means scientific, and not all corns will cooperate 100% with the schedule. The weight ranges I gave for the prey and snakes are approximate."
A link to the original thread:
http://www.cornsnakes.com/forums/showthread.php?t=50106&highlight=Munson+Plan
And a link to the Corn Snake forum itself, a great and (IMO) necessary resource for any corn keeper... The BD.Org of Corns, if you will:
http://www.cornsnakes.com/
Really, it sounds like you both need to seriously rethink your corns' feeding regiments.
As for the OP--if you wanted a bigger snake, you should've gone with a ball python... Your corn will get however big it will get, regardless of how much or little you feed it. If it's going to be small, all feeding it more will do is make it fat (aka unhealthy). If it's going to be big, all feeding less will do is make it grow slower (which MANY experienced keepers would say is actually healthier, so win-win there).
I hope this is of help... To both of you, actually.