Why not? Going into a place that you shouldn't be in is really not a gear issue but a poor judgement issue imho. BM divers can get themselves in trouble too.
How many dives are really being done these days that you can only safely do in SM or BM? Hardly any.
I don't get why people like you and AJ think that SM diving is not as safe as BM. For most dives, I don't think it makes much difference as long as you are properly trained and have the right mindset. I would love to see GUE getting into SM training... It'll be good for the industry, all these rinky dink agencies out there need more competition.
Now, as for your rebreather point. I dont think you can compare them to SM at all. Breathers are dangerous and all this 'rec' rebreather stuff is bs but sidemount is not more dangerous than BM.
I would like to do a GUE workshop or course and learn more about ratio deco and project stuff but I don't what to buy a bunch of extra gear that would never use.
I appreciate your ability to read my mind.
I don't think sidemount is inherently more dangerous, and I don't have any issue with someone diving sidemount. Heck, I have a sidemount rig and I sidemount my bailout bottles from my rebreather.
The only real risk that I see in sidemount configuration is losing a reg, you will lose 1/2 of your gas in that situation. The idea of switching regs while holding your breath in a stressful situation is right up there with unicorns and rainbows. But, if you lose a reg you should call the dive and head home anyway, so it's a manageable risk.
However, here are some cons I see in sidemount:
1. increases task loading the first few times you dive it with the constant gas switching. Someone learning how to cave dive is already tasked loaded enough, and really doesn't need the extra bit of task loading involved with learning sidemount at the same time. IMHO, beginning technical / cave divers are better served diving backmount, OR mastering sidemount before undertaking technical training.
2. Is less efficient. When I dive backmount I can be suited up and in the water in a fraction of the time it takes when diving sidemount (how many trips do you make to the water?). Ditto for breaking gear down.
3. Is frequently taught in a sloppy style that leads to damage to caves. Ever notice those twin furrow trails in clay floors? Look at the antenna that are sticking out from under your armpits to understand how they happened.
But these are just my opinion, and while I think newer technical / cave divers will be better served by learning backmount first, as long as someone isn't hurting themselves or others, and their config is safe, then knock yourselves out.