Definitely over-conservative, and on what basis?
If I dove with you, I could set my countdown timer for half what the tables allow, and ascend no matter what. Then I'm supposedly 'safer' than you because I'm not pushing NDLs as much as you are. But a friend of mine might stay on the boat, and say he's safer than either of us.
How is that different than 'blindly' following the tables? In either case, an inanimate object is giving you a guideline based on calculations most of us aren't familiar with made by people we don't know personally taking it on faith they're based in science (if only theory) and have stood the test of time well in actual practice.
It amazes me how 'graven in stone' some people take tables to be, yet how distrustful of computers some of the same people seem to be. You can ALWAYS dive 'more conservatively' and claim you're theoretically safer.
Some people dive nitrox using air tables. Some people cut their dives way short using tables.
Is there some actual morbidity/mortality data to guide this, or at least give people some idea of what risk difference is involved, or is this just a product of some people wanting to think they're 'extra' conservative/safe?
Over time, you'll sacrifice a lot of bottom time. I just want to know if there's a good reason to think you're getting anything real back for what you're giving up.
Richard.