Everest is littered with dead, exposed bodies

If you liked the article you must also read http://en.wikipedia.org/wiki/Into_Thin_Air by Jon Krakauer

It's actually only about half that price or less (in the US), unless you get into the really extreme stuff. There is a lot more to diving safety than just using the correct gas mixes. The training and procedures developed by groups like the WKPP and GUE have now taken nearly all the risk out of technical diving. http://www.gue.com/

Yes for caves. Caves are easy and safe compared to deep open ocean wrecks. Caves may actually be within the "reasonable to do recreationally" level, and WKPP is or was actually doing worthwhile environmental science too.

Outside of the US, helium is seriously expensive. I was figuring dual rebreathers, or rebreather + OC bailout. $800 in gas alone for a 100m training dive for TDI Adv Nitrox, open circuit.

WKPP and GUE definitely use teams to reduce the risk AND cost (although I have some issues with some of GUE), but at the same time, it reduces your flexibility. I really would want to only do tech diving with a group of people I routinely train with and trust, but I'd be ok with customizing our gear as a group.

Not using computers is just fucking unforgivably wrong, though. Using a computed table as your primary dive plan, sure, but you want a computer in case anything doesn't go according to plan, plus a bottom timer.

I wouldn't dive below 30m in a difficult environment without dual buoyancy on independent gas sources (drysuit + argon bottle, or twin tanks manifolded with BC on one and drysuit on the other, etc.). Helmets, especially with lights, can save your life. Snorkels can be useful if you do shore dives or long surface swims (although I throw it into a BC pocket). There are times when a big knife, prybar, hammer, etc. can be useful, and I never dive without shears and a knife. Solo dives are probably better for some wrecks (although maybe it being a solo-only environment makes it not worth diving there). Air at 30-40m is probably ok, although trimix at 40m+.

I recently got back (almost exactly a month ago) from a month long climbing trip in Nepal with some friends.

We had three guides, all three of whom have climbed Everest multiple times. One of our guides, who has summited 5 times, described Everest as his "bad habit".

As a relative newbie to high altitude mountaineering (the highest I got was ~19,850 feet), climbing in Nepal was really, really hard. You are never warm, the food sucks, camping for long periods at high altitude sucks rather a lot, you are never clean, altitude sickness sucks, pooping in an 8" hole in the ground sucks, not eating much protein sucks, but… the views are spectacular, the people you meet are amazing, the place itself is awe-inspiring, the wildlife is interesting and diverse, the peace of the place is fantastic, and the mountains… well, the mountains are something special.

I can see why some people spend their lives chasing summits, and I can also see why some people, having seen their first summit, turn away from the mountains forever and never come back. While we were in Nepal, within two days of our summit push, our head guide had two friends die. One died on Cho Oyu in an avalanche while traversing a glacier. The other died on a relatively unknown mountain in Tibet. Both were world-class mountaineers. These were people who no mountaineer in the world would accuse of being irresponsible, inexperienced, unprofessional, or, even, unsafe. They were serious mountaineers with long resumes and respected records.

That said, exploration is always a serious business, and when you're out at the sharp end, sometimes you get cut. Without these people, however, and the part of humanity which they represent, we would never expand our experience of what it is to be human and our knowledge of the space around us.

Even with Mount Everest, where the experience has been honed to the point where there are professionals whose entire job it is to make sure clients make it to the top… it's friggin' hard. Having been to nearly 20k feet, I have nothing but respect for people who can make it to 29,029 feet. Climbing that far is hard, no matter how you do it. I can only imagine the feeling of being on top of the world, and quite frankly I'm not sure I'm up to the challenge, personally, of tackling Mt. Everest. I will certainly never make fun of anyone who has climbed that mountain.

Given the difference in oxygen between where I got to and the top of Everest, I don't think I can comment on the impairment of cognitive facilities climbing Mount Everest imparts. However: there's a good reason most responsible climbs leave a controller in radio contact from base camp or Camp 1 in charge of final decisions. Oxygen deprivation is a serious impediment to rational decision making.

So, yeah, go ahead and don't climb where you don't feel comfortable. Just don't go judging those who do without having done a high climb yourself.