First off,I use a crossdraw-a SASS legal crossdraw. By that,I mean that it doesn't depart from the vertical by more than 30 degrees. This rule is in place to prevent the holstered gun from sweeping those behind. That,plus the "crossdraw dance",make crossdraws as safe as straight draws. If someone doesn't do the dance,they get DQ'd-it's that simple.
At your next shoot,watch some straight draw shooters pull their guns. I think you'll see that a lot of them "drag" the gun from the holster,meaning that the muzzle is pointing backwards as the gun is being drawn. Now,this is a legal draw,and I've never seen anyone warned for doing this. So,using that example,a crossdraw done correctly from a legal rig can be safer than a legal draw from a straight hang holster,as the muzzle is pointed downrange as the gun is drawn and reholstered.
Crossdraws have been around since this game started. There are those who would outlaw them in a heartbeat if given the chance. But,for now,crossdraws are allowed-they just have some caveats that go along with them. If you're shooting in a SASS affiliated club,then SASS rules should apply,including the 30 degree rake of a crossdraw. If you see a rig that you think isn't legal,bring it up to the RO. If he won't do anything about it,then find another place to shoot.
SASS is shoting sport where a lot of things could go wrong,but rarely do. We must each be vigilant and call safety infractions when they occur. If we don't,then we don't feel comfortable,and the person breaking a rule or being unsafe isn't made aware of the problem-neither of these things is acceptable. Learn the SASS rules and continue to be vigilant,but realize that the current rules are the result of 20 years of experince.