I Have done a bit of tweeking to my P-11. The "fluff and buff" that Keltec groups talk about. didn't shorten the trigger pull, but made it a nice sweet long revolver style da. Also the overall consesus from what i have read, is ..don't change the polymer guide rod on the keltecs. yes, there were apparently problems with Glock polymer rods in the day, but not with the keltecs. also the fear is more wear on the gun (peening at the slide, more wear to the barrel "lug".
The various fluff and buffs i have done on 3 keltecs now have worked well to really smooth the pull. i have a couple of good links, but go here....
http://www.ktog.org (go to the bulletin board) .....and try what they have. they also have the links. The "golden Loki" instructions are the most comprehensive.
Hope this helps. ( i love my p-11 now that i put some small tlc into it) there is also some.....selling of after market trigger mod stuff, i haven't tried it, but have been intrigued.