I just noticed, a couple of months into my biweekly campaign, that the attack bonuses for Labyrinth Lord are a fair bit different from Moldvay/Marsh/Cook.
In Moldvay, starts at thaco 19. Fighters (&elves dwarves etc) progress:
4: 17
7: 14
10: 12
13: 10
Clerics & Thieves use the same values, but progress at 5, 9, 13, and 17. eg
5: 17
9: 14
13: 12
17: 10
Magic users are same again, but progress at 6, 11, 16, and 21, eg
6: 17
11: 14
16: 12
21: 10
LL seems a bit more like AD&D, with much more frequent steppings.
Everyone again starts at thac0 19, or attack bonus 1 if you prefer.
Fighters, elves, etc progress...
3: 18
4: 17
5: 16
6: 15
7: 14
9: 13
10: 12
12: 11
13: 10
So I guess It's really the same progression but "smoothed". I guess I prefer the LL table.
Similarly clerics & thieves are:
4: 18
6: 17
9: 16
then a strangely fast advancement..
10: 15
11: 14
12: 13
13: 12
This time there are some interesting aliasing effects with 6 being behind and a quick set of jumps around 10. But all in all it's similar to the materiel, I just didn't realize how they stepped differently until I started writing this post.