Well, some people choose to brumate their snakes, which gives the snakes the inclination through climate change that it's breeding season. However, there is nothing wrong with breeding them without the snakes having been brumated. In my opinion, if they breed, whether or not they were brumated doesn't really matter.
Mostly people brumate for secondary reasons other than for the snakes sexual well-being, it seems. It's usually around the holiday season that people put their snakes away and give themselves a much needed break for a couple of months. =P
Also, in the Corn Snake Manual, Kathy Love states that the sperm and ovum production increases while the snake is in hibernation. I guess because the snake can actually take the time to develop those systems instead of diverting key energy sources towards hunting, hiding, etc during the normal season.
Well, funny story really happened with my breeding pair. My adult female escaped on me last July, and over-wintered somewhere under/within my house..and I found her outside in my flower bed in March. I don't know if she really hibernated, or stayed warm enough to stay active throughout the winter months. It took a few weeks for her to get receptive enough with my adult male to actually breed with him. And that was almost a month ago that their last intended breeding took place. Right now she's looking gravid and close to shedding. So we'll see how her first attempt at breeding was, and how many fertile eggs I get out of it. =)

Here's a pic of her last week, she's getting more cloudy and her skin is starting to show between her scales.
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~*Taceas*~
rain@mainecoon.net
"And shepherds we shall be, for thee my lord for thee. Power hath decended forth from thy hand so our feet may swiftly carry out thy command. And we shall flow a river forth to thee and teeming with souls shall it ever be. In nomine Patris, et Filii, et Spiritus Sancti." - The Boondock Saints