I am of the opinion that the convention should be conducted in the following manner:
All delegates are bound to their candidate going into the convention. All candidates who received at least 1 delegate are eligible to receive their delegates votes. The first round then establishes the order of candidates based on the number of delegates. If one candidate receives a majority - that is the nominee.
If after the first round there is no nominee, the candidate(s) with the fewest votes is removed from the list of eligible candidates. The delegates that were assigned to that candidate are then unbound and can vote for any other candidate. However, they remain bound to that candidate in subsequent rounds of voting until their new candidate is removed and they are again unbound. A delegate may also abstain but once abstained, they may not vote for another candidate in any subsequent round.
So on the 2nd round, the delegate count is the same with the exception of the delegates who supported the lowest tier of candidate. They then get to change their support. At first, this will only be a handful of delegates. But each subsequent round of voting will reduce the pool of eligible candidates and will concentrate the delegates behind a single candidate.
The 3rd, 4th and subsequent rounds would be also conducted in like manner until there is one candidate with enough votes for the nomination. In the rare occasion when there is a large dislike for the field of candidates, one would expect the “abstain” block of delegates to get to the point where it has the majority of votes. At that time, all delegates are unbound and can vote as they please.
The actual rules are far more complicated, as I’m sure you would guess.
https://cdn.gop.com/docs/2012_RULES_Adopted.pdf
Delegates are bound for as long as their state rules say they are bound. If your state says one round only, you can vote as you wish starting in the second round. That buys a lot of early, and possibly decisive, attention in the event of a contested convention, which buys favors. If your state says you are bound for eight rounds, then you are bound for that long too, which buys a little extra attention in the primaries and may make your state the deciding vote if it takes a lot of rounds to get a nominee, and that buys favors too.
Note (Rule 16): votes cast in violation of state law or state party rules are counted as if they voted for the candidate they are bound to, and the delegate is “deemed to have resigned”. Bound delegates truly are bound to vote as mandated by their state rules.