I agree...as it sounds more like impatience than pulling; tie him to a good sturdy tie post, perhaps with a neck rope, and make a habit of letting him stand there for a good chunk of each day. A horse only gains patience at the tie out by being tied and not getting off the hitch for being antzy.
IF he starts to pull back, as suggested, unless he seems in immediate danger, do not release him...once he figures out that setting back actually gets him off the hitch, it becomes ingrained habit.
However, that said, if he does pull back, get an aussie tie ring, or the like, and use that to desensitize him to being tied, and teach him to 'spook in place'. If you get the Aussie Tie Ring, it will come with video, and instructions on how to use it. I love the concept of the tie rings, because the horse can set back, release a bit of line, and figure out that being tied is okay, simply because his fight instinct is 'shut down' by being able to get a release, and eventually they don't even set back anymore.
However, that said, "some" horses do figure out that they can just keep backing up and release themselves anyway...which would defeat the purpose of the tie ring. For those I teach them to ground tie, and when I'm ready to solid tie, I start with looping the lead over the fence, and progressing to eventually solid tie.
"The ideal horseman has the courage of a lion, the patience of a saint, and the hands of a woman..."