Ugh, it's horrible hearing all the horror stories people have about loading, What should really be a simple training exercise turns into a war with the horse because people don't have patrience or control over their temper. The horse is always the one who loses.
I have seen some ppl just forse a horse in, shut the doors and haul it wherever it needed to go and not even give the horse a chance to warm up. I would like my horse trailer to feel like home.
My theory on floating... The float isn't home, and I don't want my horse to think it is. It is a modeof transport. I want my horse to learn that they go in, we go somewhere, and they get to get out. I never load and unload my horse without going somewhere. Even if we have to use a butt rope, or it takes a while to load, I never unload and do it again. That isn't a reward. They get on the trailer, what you wanted, and instead of going where you're headed and getting off, they are made to do it again. Just doesn't seem like the best way, in my opinion. The journey and getting off at the end is the reward for getting on. Using this method, every horse I have/had has become a self-loader within a month, and stayed a self-loader for the time I've had them, and the ones i'm still in contact with are still self-loaders.
I also beleive that most floating problems are actually leading problems. If you ahve a horse who leads well, then you should be able to lead them anywhere. They should also know the appropriate restion to pressure, I.e. Not rearing up, hitting their head, flipping out. Apply pressure - Horse moves forward - Release pressure.
An important note too is to always stay calm. Getting angry or frustrated is the absolute worst thign you can do. Act like you have all day and it will take five minutes; Act like you have five minutes and it will take all day.
That's just how I do it and how I see it, and until I find a horse it doesn't work on, i'll stick by it 100%.