Well think about this, the majority of divers on here are the usual clear springs suspects, athens, etc, if you need helium in either of those places, your doing something wrong.
About the only place you can put helium to work locally is Travis, so if most of these swampers are the CSSP breed, they don't want to dive trimix, no need, so strike one, the diving in the area does not demand trimix.
Ever price what shops charge for mix around here? Helium is stupid expensive from a shop, I understand why, but understanding doesn't fill peoples wallets with money to spend on gas, places where helium is in demand is cheaper than getting mix around here, so strike two, cost.
How many tech rigs have you seen running around the lakes, I mean true tech rigs, not these DBL AL100's stuck on a 100 lbs double bladder wing or "tech BC" with hoses sticking out all over the place, now don't start flaming there is nothing wrong with that, if you want to dive that and it works for you thats fine, but those rigs reflect that person has a limited amount of training (most of the time, not always) and chances are they aren't even suppose to be doing deco let alone dabbling in the black arts, so lack of tech divers in the area, rather the vast minority, so there is 3
Computers, how many divers on this board fly by wire only and couldn't cut tables? if thats your diving style, thats fine, but those folks are going to be less likely to go to mix due to the high costs of mix computers, there is another.
Gear costs, to really dive mix you need to be on doubles, deco mixes so more regs and bottles, and you HAVE TO dive dry, not many people are willing to invest that amount of money to dive lakes when you don't take that rig to cozumel.
Lakes, who the hell wants to invest all that money to dive deep in lakes, its nasty down there, you gotta be nuts to want to dive that deep in travis, vis sucks, its cold (but its fun!) thats a hole lotta money for even a fill if you already on the gear to look at a mud plane in 50 degree water with 6" of vis
There are mix divers that lurk on this board, I know of at least one that is certified, actually I know of a few that are certified, I also know of some that dive it the same way I do, self educated - (they hide all that information in books you know) that do not speak publicly about it, so I will not disclose who they are.
So I would be more suprised if people responded then not, the local mix divers probably dont' dive much local and use mix only in good diving spots that require it like caves and wrecks.
Most home brewers, and yes I am not the first, nore are we the only ones, keep their stuff a secret, I probably should too as I really dont' want someone on here reading this and going "he does it, I can too" and going out and killing himself, some may view what I do as wreckless and irrisponsible, but those that know me know I'm very conservative and very calculated on how I perform my dives, I'm not a risk taker. I wouldn't be suprised if most of the local mix people are home brewers without certifications, this is a very common practice in other parts of the country where people are more realistic about things, cause man I tell you guys, from all the crap I've seen in my short diving career a card in your hand does not make you a safe diver, not by any measure of the word, there is a big difference between knowing, and doing, every time I come back from florida my eyeballs ahve to get pounded back in from them popping out at teh stuff I see, no wonder they have to do body recoveries, ok off track there sorry.
My point is if most locals are home brewers, chances are a lot are not certified and will not come forward, but they are out there, I know of others, certified and not.
