I go clipless with every knife I own. I was actually thinking about making a thread based on my experiences with this. That is many folders come with loctite on the clip screws and I've gone through two torx heads so far because they strip them. I had to spend about 20 minutes with some pliers today to get the clip off my new Boker Wharcom.
I think the clip makes it comfortable to carry the knife, but I don't like how it feels when you use the knife, when you reach into the pocket or the fact that it shows everyone you have a knife. My knife is never seen unless it's being used or I'm with like-minded friends and we're just showing eachother our latest knives. To me knives are so, so much more ergonomic without the clip. Maybe someday I'll find a clip that's comfy enough to leave on (Spyderco's Wire Clip comes close), but for now I think knives feel too much better in hand without one to consider it.
I've carried everything from a Kershaw Chive to a full size Manix in my pockets without a clips and it hasn't presented too many problems. For larger folders like an Endura or Opinel #10 I'll often put them vertical next to my wallet. Certain folders stay put there better than others. Most of them just go in my right front pocket, like my Storm, Leek, Wharcom and thin SAKs. Some I'll put in my wallet like my Buck Hartsook and Alox Bantam. With tighter pants something the size of an Endura will do a good job staying vertical in my front pocket unless I'm really running around, so it's still pretty comfortable.
Every knife I've owned felt too good without a clip for me to go back. The first thing I do when I get a new knife is reprofile the edge and take off the clip, won't even carry it any other way.
I think people should definitely try it with smaller folders like the Spyderco Delica and anything smaller they make, the Subcom series, Minigrips, Leeks and other smaller folders. Even laying horizontal in my front pocket the Leek doesn't bother me and it's big enough to get a four finger grip. The subcoms are smaller than many keyless entry systems on peoples keychains and they're very flat, not much of a reason to not try pocket carry IMO. The Byrd Robin would work great too.
