Well, my mare is a big one for pulling back. I thought I had her sacked out on it, and tied her to a low ring about 4 feet off the ground. In the few seconds I was out of sight, she managed to get the rope over her nose, and wrapped around both front legs. I came around corner of barn to find her tied with her face to her feet and freaking out. I had to cut the lead rope to release her. She learned through this experience to not only pull back, but then leap forward throwing her front feet up (and sometimes over).
Here is what I have learned:
1) Make sure the distance from the halter to the rail is short. Yes, if she wants to pull back a short lead will make them react, but if it is longer than your forearm, they can (and will) get it wrapped over their head and/or legs.
2) I use a neck rope like the one described in this forum. She can pull on it as hard as she wants.
3) I would recommend a rope halter (not leather or webbing). I think the webbing halter (and I tried one) provides too much surface area across the poll, so there isn't an immediate consequence to pulling back. When I shifted to a rope halter to train her for tieing, some of the pull back intensity decreased. Also, right after a big pull back, I was working her with a halter and could tell her poll was tender, so - for me - this helped.
5) Body rope: I like them for training. Make sure they have a big hondo so they release immediately upon the horse giving. I've seen a good video of this on YouTube but couldn't find it. As discussed before, rope goes over girth area, through front legs and through the halter loop. When horse pulls back, they self-cinch and react (See #1 above). What is difficult about this rope for me is my mare's tendency to rear/leap forward after she sits down. If she gets the rope off to the side, or around a leg, my problems would increase exponentially.
6) I don't like the inner tube option. With my mare, it seems like if she gets any give at all, she goes harder and harder, so the "spring" of the tube just sets her off more.
7) One of my training challenges with this is she won't do it if I am standing anywhere close. So, I can't stand on the rail and work the rope, or do the "approach/retreat" stuff discussed earlier. So, I have to tie her and go hide and watch.
8) Learn to tie knots that can be released after lots of pressure. Bowline knots, etc. are designed so they can be worked loose after a big pull. Others tighten to the point they cannot be undone (or take a lot of time). Use easy to untie knots anywhere the rope may be pulled.
9) When I tie her, I use a clove hitch around the hitching rail (with a quick release loop), then tie a bowline around the rail at the end of the rope. If, somehow, she broke the clove hitch, she would still be tied.
10) Since I can't stand there and create a situation where she will pull back, I have to walk out of sight, hide and watch her. That means she basically has to work out the issue without my intervention. This makes it challenging and somewhat risky for her. I don't like it, but can't think of a better way. If I keep rushing to the rescue, I'm giving her the reward she is seeking (company), so she just pulls back harder the next time.
11) Have a very sharp, long bladed knife readily available. If you need to cut the horse loose, you will want to be able to do it in one movement. I like one that has sharpened serrations on it.
12) I think (knocking wood), that with these "techniques" I've solved my pull back problem, but my mare seems to have a knack at finding new ways to be challenging. Now she stands at the rail and digs to China. So next we add hobbles (after making sure she is trained to them).
I'm not saying or implying my way is "right." Its what I've had to do to get this crazy lady to stand still.
Couple of useful YouTubes:
(4 Part Series)