About the Molyneux video: It starts with some unfounded statements. When he starts to analyse it becomes a bit ridiculous: Colorado ofc did NOT choose to not have a preferential vote because of Trump announcing his candidacy. Back then in August 2015 he was still widely regarded as a joke candidate and the establishment wasn't worried about him at all. Anyways, the simple reason CO (like WY and ND) did prefer to not have a preferential vote was the change of rules the national GOP made to the process. Unlike in all races before, the national GOP changed the rules regarding delegate binding! And that was a reaction to Ron Paul's strategy. The new rule: All state GOPs have to bind delegates according to the respective preferential vote. Before March 15th that has to be done in a proportional manner, after it is allowed to be winner-take-all.
This new rule was clearly because of Ron Paul. Remember Lousiana and other states which held a preferential vote in 2012 and Ron got under 10% of the vote while later on he won majorities of the delegations! So there never was any national GOP rule that you cannot hold a beauty contest (regarding the preferential vote) like some states always did, in all the years. New national rule was clear: Delegates have to bound according to the preferential vote. Mandatory.
So what did some State GOPs with a tradition of beauty contests do? CO, WY and ND chose to not hold a vote at all. A move unexpected by the national GOP btw. So ofc they could not bind any delegates to a non-existing preferential vote and the process in the 3 states is simply caucus / convention, get your delegates from the countries or districts to the state convention and vote on delegates there.
Trump's Campaign thought they could skip that. CO, ND, WY. The next weeks will tell us how much of a blunder that has been. Maybe Trump will win big in NY + New England States + CA and he doesnt need them at all - and maybe he will only come short of a few delegates on the 1st ballot and he will lose because his campaign had no ground game at all in these 3 states. 94 delegates were at stake in the 3 states, as of now it seems Trump won only 1.