I did carry my knife tip up, electrical taped to my LBE when I was in. When you had a 60+ pound ruck sack on top of a LBE that had a buttpack, poncho, two canteens, full ammo cases, a compass and whatever else, including a M16 in front of you, it was damn hard to reach a fixed blade on your web belt digging into all those straps and whatsits. I switched off that style when I got an Sypderco Endura with serrated blade. It was super easy to clip to gear and be secure. Of course Leatherman wasn't really that big a name then, Gerber just came out with there multiplier, SA was still popular but bulky. Most grunts only kept a multi tool on their belt in garrison. But out in the field it was in a pocket and not easy to reach with full kit. MOLLE kind makes that easier now.

Sort of the same issue with low riding thigh holsters. You see this in a lot of movies and psuedo-crime/LEO shows on tv. That looks cool but its reality with operators or real LEO. It flops around way to much. A low ride might be offset off the belt a bit but not dropped low thigh. If on the belt its more than likely flush. I do know a lot of tactical teams now, thanks to MOLLE gear and better safeties, that put the sidearm on their weak side chest almost horizontal, so grabbing it is like putting your hand over your heart. It's high up on the chest when in CQB, or low crawling or laying behind cover.