“Trump will carry Iowa...providing nothing weird happens.”
There’s the rub. A caucus system. Your neighbors see who you caucused for. And out of staters can flood in same day and join in, like they did for Obama. Notice how Obama won the Caucus states and Hillary won Primaries?
Iowa can provide any result needed.
All of this whining about the Iowa caucuses come from people who don't really understand them. The January caucuses are precinct-level votes. Only people who live in the precinct and are party-registered can vote. The meetings are open to the public, as they should be.
After that comes the county convention, whose members are chosen at the precinct meetings. The actual state representatives to the national conventions aren't chosen until the state-wide convention of those chosen at the county conventions. That's why you often see the Iowa delegation to the national convention voting differently from the results of the precinct caucuses.
I think it's better than primary voting, particularly open primaries.
My state (Nevada) is a caucus state. Before voting, if you wish, you may speak on behalf of your candidate but you do not have to. And voting is secret. Your neighbors will not know you voted for, unless you wish to tell them.