Have you ever worked a cow?
There are many ways to catch a hard to catch horse. The only one that has worked consistently for me is blocking.
I detest having to feed a horse to catch it. I never treat my horses if they run away. And they don't run away. Odd.
So... Blocking. It's not following, and it's not chasing. Some people touched on it. The concept comes easier of you have worked stock, wether it be wild horses, cattle, sheep, etc. Basically, you can control an animals direction by changing your location in relation to their eye. With horses, it is more often their shoulder. So, the idea is, if you get in front of the eye, you are blocking. If you are behind the eye, you are driving. The distance away determines the force you apply, therefore the speed of the animal. Getting up close will speed them up, further away lets them relax and slow down.
So, if your horse walks away in the paddock, block them. If they go left, you get in front of their eye to the left and turn them back. It should then go right... You get in front of the eye and turn them back. So on and so forth. You keep them turning, don't let them rest. I generally stay fairly far back and let the horse pick the pace. If they run, I back off more butkeep blocking.
Now, if the horse stops of its own accord, you also stop. I let them think for a second, then I try walking up to the shoulder to catch. If they move off, I drop back and keep blocking.
Never had it fail. You aren't chasing, so you won't scare them. You aren't just following, which gives no incentive to change the behaviour. You are still working them, and the release comes when they stop, face up to you and are caught.
Oh, and just a note, I never just 'hang out' with my horses unless it is bath day for a show, and they all still face up and stand quietly to be caught. I don't think it is needed.