Just because it's "pretty standard" doesn't mean it's smart. I get that most pretty fish people don't have the training to understand why it isn't the greatest idea
I think you're totally missing the point that Vladimir was making. I'm only unsure as to why. The point he is making is that as it's "pretty standard" practice and people aren't constantly being airlifted off these boats, the implication is that it's "pretty safe". Anything that's "pretty safe" is in my book OK to do.
Diving has intrinsic dangers, and although these can be minimised they cannot be eliminated. Every dive is a balance of risks and judgement. I place the dividing line where I feel comfortable, and I have countless times performed the dive the OP described, admittedly not quite in the manner that he approached it, with much the same basic recreational equipment. I have also dived in the same place to deeper depths and/or for longer durations with very much more involved equipment. I always estimate the risk I'm exposing myself to and equip myself accordingly. That doesn't mean I'm immune from risk, and if unforeseen events conspire sufficiently severely I shall be in trouble. That is the case on every dive, "tech" or "rec". As I said above, I try to keep within my personal comfort zone, which may be quite different from someone else's.
The above applies to dives I am making solo, or with companions whose skills and behaviour I feel comfortable with. When I'm teaching I apply completely different standards, not particularly because I feel the need to show my student how it should be done (though that is so) but because I'm now diving for two, I'm carrying gas for two, and my companion certainly CANNOT be trusted to behave rationally.
The dive the OP was describing is, or should be considered a tech dive and treated as such. Just about all the dives done here in Northeast are deeper than 100 feet so they are too. If you get on a boat without a reel, lift bag, backup gas, people will look at you funny at the very least, and most operators wouldn't let you dive like that
>100ft does not make a dive a "tech" dive, whatever that is. Dives MUCH deeper than that are routinely performed by British divers with only basic (British) training. Training which is much more demanding than certain basic US tech courses. And the dives are never undertaken in a vacuum, but mentored in a club atmosphere by experienced divers. The dividing line there between "rec" and "tech" is pretty fuzzy, but most dives there considered to be "rec" are definitely regarded as "tech" to the west of the Atlantic.
In England lift bags are banned by some operators for certain dives, where they don't want people stripping wrecks. DSMBs however are pretty well mandatory. Here in "pretty fish" territory in Belize I rarely ever take a lift bag, but I take a DSMB on every dive.
I don't know whether your reference to "pretty fish divers" was intended to be offensive, but I'm afraid it did rather come over that way. Offensive and conceited. Just because people choose to make a certain type of dive does NOT mean that it is the limit of their training and experience. Just because people limit the equipment they take down with them to what is needed for the dive does NOT imply that they don't possess or know how to use more elaborate equipment. I am perfectly happy taking a single tank in a conventional recreational BC on a dive for which I consider no more is needed. For a more demanding dive I'll take more elaborate equipment.
One question - was the fact that you used sidemount gear in Fiji relevant to your safety on those dives? Just wondering why you mentioned it.
And you must tell me the trick to feeling that you never went in the water after diving CCR. Perhaps if you dive a very high pO2, which would suggest you don't do many CCR hours in a day. On long dives I now don't go above 1.2 or sometimes 1.1 - even 1.0 when diving repeated days - and I always know I've been diving.
