Check out the "the Hunting Public" videos on youtube. They dont talk about saddle hunting, but thats how most of the hunts they do are done. you can learn a little from just watching them.
There is a saddlehunter forum that I joined and is pretty informative. I ise the recon saddle. Basically seatbelt webbing that forms two hammocks. One for your butt, the other for your back. Much cheaper than some of the single seat style. I am an impatient hjnter so I am only good for about 4-5 hours in the tree before I have to get down and move.
Probably more from people not knowing what they are doing or enough practice at lower levels. I started 2 years ago as a public land access way of hunting. It is much safer than the average climbing stand and strap on stand as most people do not use safety gear when hunting that way. All my life I never used a harness while in a pallet or strap on stand. A fall from 15-20 can mess you up. With tree saddle hunting you are always strapped to the tree with a climbing rope. You put your first step on, attach lineman's rope to tree and start up the step. Once on top attach your tether to the tree and use that as you go up always attached to the tree and no more than a few feet drop if your steps fail. I feel much safer tree saddling than having a climbing stand and with less weight to carry.
Saddle hunting is good if you walk in a long way and must take your stand back and forth every day. But like all stands they won't work well on every kind of tree. Your climbing steps are more important than the saddle. Research window washer rigs like used on high rise buildings. Made my own much more comfortable cost next to nothing can hunt much longer. Spend your money on the best lightest steps you can find. And try to avoid a all web saddle they squeeze you and it wears you out. A limb or platform to stand on from time to time is critical for a all day stay. If your over weight or not in fairly good condition saddle hunting might not be your best option.