Okay, I'll go first:
I've heard a lot of excuses from sandbaggers for why they won't upgrade, most of them are something along the lines of (and I'm definitely paraphrasing, LOL) "I won't win all the races in the next cat up because...", and then it's usually something about not having the time to train to be "competitive" (to the sandbagger "competitive" means that they win), or being too old to be "competitive", or not having the natural talent required to be "competitive".
There's no excuse for sandbagging. It's not like one person has a special right to win all their races.
Who cares if you want to train for longer races or not? CURRENT results are the basis for upgrading. Just because you predict that you won't dominate the next cat. is no reason to sandbag. If you've won some races it's time to move up.
Worried you won't win in the next cat.? Get over it.
If constant ego stroking is what you need then maybe cycling is not the sport for you... try Little League, with your superior size and strength I'm sure you'll dominate all the children there.
Although I'm sarcastic by nature, don't take it personally... I'm sure you're a great guy/gal but you're making a bad call by not moving up. Sandbagging is bad for the sport and hurts everyone.