I just think you maybe somewhat missed the point in ATLDave's post. It's all about risk acceptance on both ends. If you think (rightly or wrongly) that your risk of needing to clear a stoppage in a split second is crucial, then you are probably willing to accept the risk of pulling the trigger behind a squib load. Of course we could debate all day long the relative risks...but I think it is pretty safe to say that kabooms are more likely than needing to clear a malfunction in a life-or-death situation someday. That's all he meant. For some, they know that, and accept it. Others do it for matches, and accept it. Heck, it is fun to TRB super-fast! But others may not understand the risks of some failure drills and OVER-estimate the risk of an actual stoppage in a firefight that they might find themselves in. So in the interest of everyone involved, it is good to point that out. We don't want some new shooters to come read this thread and think "my goodness! I have to start practicing lightning-fast tap-rack-bang drills!" and go out and hurt themselves.
The "would you rather have it and not need it or need it and not have it?" rhetoric only goes so far. In some issues, it makes sense, like carrying an extra mag, you probably will never need it, but it is zero risk to carry it. Carrying a gun is itself an assessment of risk. I don't have any more concern than the next guy that I will need it, but after studying the risks and learning safe handling/carry techniques, the risk is near zero, and it is worth it to me to carry a weapon. But I think if we don't stand back occasionally and assess these things, we just carry and train blindly for any perceived possible risk, real or not, then the training may suffer, because you can spend more time worrying about more likely scenarios, and we may be perceived like overly-paranoid gun nuts by some and it does nothing to further our cause.