While having dinner with Susie this evening [we eat early], the following thought occurred to me. Suppose Trump comes into the convention with 1250 pledged delegates -- a bare 13 over the 1237 mark. Paul Ryan calls the roll, and when the all the states have been polled, Trump has 1230 votes. Everyone in the world has been keeping track, and it is clear that 20 delegates have not voted. A quick check reveals that they are not in the hall -- they are "sick," something they ate, and are in their hotel rooms.
Ryan has a good deal of power, either to suspend the vote, if he chooses, while they are dragged into the hall, or to wait a proper ten minutes and then declare the first ballot concluded with no one getting the required majority. On the second ballot, 200 "Trump" delegates defect, as they are permitted to do, and Trump loses decisively.
Does anyone want to make book on what Trump might then do?
This thing is far from over.