I use it as often as I can recall, when it should/could be applied. When 3 foes attack with spears, spear like pole arms or shortswords in a hallway, being limited to 1, maybe 2, slashing sword, mace or axemen brings home the fact a larger damage die is NOT always king.
If there is one thing that I really didn't care for in later edition/mini based combat, it was the idea people just move freely THROUGH each other or that bases touching was melee range, rather than dagger/fist type close quarters. What little use I do with Minis in AD&D 1e is based on 3' or yard squares, and generally there is a simular space desired between foes with medium length weapons. By necessity, this means some rounding off of AOE spells, weapon space required, ect, but it isn't too bad at all. It's off topic a bit, and I know minis are by no means universal amongst old schoolers, but I know plenty that do use them, and did long, long before I ever did. I avoided them like the plague for mant years.

6, 9, or 12' halls work just fine though If one does want to try it

. I rarely use them these days myself, but as always was true, some players & DM's will enjoy them, & they DO help somewhat with visualisation. When they come to detract from imagining the scenes, and you are just playing a complex board game, it's time to back off them.