I already have taken that class. It was cool...would have been better if the teacher had known HOW to teach.

This topic has been done to death, but valid points are always brought up.

No, as far as anyone knows there is no scientific proof against housing snakes together.
Yes, it is a personal choice whether or not to do so.
Yes, MOST snake keepers choose to house their snakes separately for many reasons.
No, the OP is not forced to separate his snakes. No one is.

The reasons for housing separately are mostly for the peace of mind of the keeper. Separate snakes mean easier record keeping of defecations, sheds, feedings, refusals, and the like. It also means less Chance of having to take multiple snakes to the vet if one gets sick, and it means the ability to control breeding.
I am sure there are many snake keepers who have housed multiple snakes together and had no problems...even successes. But that is beside the point. The people who house separately, and those who house together, do so because it works well for them and their snakes.

Bottom line: for new snake owners who don't know the little details and the ins and outs of snake keeping, it is most often best for their snakes to be housed separately while they learn.