Don’t forget that many delegates bound to vote for Trump will hate Trump! In some states the delegates are chosen by the state Party; the Primary only determines for whom those invariant delegates are obligated to vote.
So there will probably be a Republican convention in which a majority are bound to vote for Trump … but a majority do not want him to win the nomination!
This viewpoint is much too black-and-white.
If Trump has 60% of the delegates’ votes there’ll be nothing to be done, but if he has just 52%, say, it would be easy for GOP lawyers to swing a few votes. If nothing else, bound delegates could simply violate their obligation (and be viewed as heroes by many).
But they probably won’t do it. Too much risk they’d further antagonize the masses. And the same reasoning applies if Trump has 48% instead of 52% – many people would feel swindled if Trump were even near 50% and still denied.
(And if they don’t pick Trump, then whom do they pick? Cruz will be in a strong 2nd place, but he is also actively disliked. To pick someone “not on the stage” would be too blatant a repudiation of the process.)