80% + of the time carry tip-down.
Have had one pocket-partial-deploy that I can remember.
EDIT: couple other instances remembered during writing, referenced below.
One time I had a tip-up front pocket carry partially open (3-4 years ago with 1st gen Brous Bionic), penetrate the inside of pocket fabric and outside of pant leg material. Was a b*tch getting partially opened knife, hooked/penetrated through two layers of fabric, out of that pocket (in a moving vehicle). Did not cut myself, but got my attention :-o Triangular shiny knife tip penetrating proud just above my thigh, was somewhat come to Jesus moment :-/
I surmised that the knife had worked its way up in the pocket a little, then down with the inside fabric of the pocket catching the flipper tang while at same time or immediately afterword being pushed up in the pocket while sitting/bending. I was sitting in truck when it happened, at least that's where I noticed it (could have happened getting into seated position ...).
I also tend to carry IWB (both folders & fixed-blades), and worry about this same type of thing when it comes to consideration of folders for IWB. In general, I am leary of any tip-up carry with pocket-clip attachment where the tip of the blade is not covered with a fair portion of the handle scale (Bradley Bowie for example of good coverage vs say Brous Bionic that poked outside my pocket that one day). Then again it might just have been the flipper-tab that caused the situ I experienced.
The vast majority of my life (at least since pocket-clips) I have preferred tip-down from a deployment and safety standard (some early and daily carried Spydercos were tip-up like my 1st gen Catcherman, and as I write .. now I can remember a few instances of that knife partially opening attached to my wader-belt). So, it seems my opinions (preference for tip-down carry) are quite possibly based on decades old experiences I have learned and sometimes forgotten (do not recall a first thought, but have firsthand basis & experience).
In general, it been my opinion that tip-up really was the product of the newer flipper generation (knife withdrawal finger-indexed-flipper-tab), and from a knife=tool standpoint (to me a flipper offers little purpose from a tool perspective except as a pressure-point-magnifier and/or bottle-opener ;-) I have been fairly selective/limited in flipper ownership, so a resultant limited recent experience with tip-up carry & use (recent being last 10+ years).
I mean no disrespect to anyone's likes or preferences, these are just my experiences related to the OP question and presented here simply with intention to help. Hopefully, something here of use to others.