Art,
I agree with you. If I am with one of my pet rifles I'll take farther shots. I've got an old 375H&H that just can't miss. The other factor is a good range estimate. I become far more brash and debonaire if I know exactly what the range is IE a range finder. The reason most people miss is either under or over estimating range. If the wind is calm and I have a good rest I can call my shots fairly reliably past 450 yds. That does not mean that I'll shoot big game at those ranges.
I like most hunters have taken those last afternoon desperation shots at galactic ranges. It takes experience and disipline to not take those shots. especially when you know that you can probably connect. Probably isn't really good enough.
Whats the old saying "Good judgement comes from experience, experience comes from bad judgement"
If you never try you'll never know