Wiki question: location and spawn percentages

[Goregasmic]

Googled this and couldn't find anything at all.

I use the wiki a lot and try to contribute as much as I can and I've been puzzled by something for a while. The location line for a mob entry goes like this:

Location (map): xx% @ (coordinates)

This is pretty self explanatory but for the % part I've noticed variance. For most named mobs it is the chance it has to spawn but for a small but significant number of mobs it is the percentage it has to spawn at a given location. Like the necrosis scarab in sebilis has 33% listed as he can spawn in 3 different spots but for having camped him before I know his actual spawn chance is around 3% (or ~9% per round).

Is there an actual template convention for this?

Speaking of template convention... is there such a thing? I kind of noticed mob entries are supposed to stay somewhat clean but some also have semi elaborate guides on the "front page" while such guides are kept in the discussion section in other entries. Personally I try to put hard and useful info on the front page while keeping speculation/partial information to the discussion but sometimes even partial info can be relevant. Are there good practice rules for this?

Thanks.