It is set to 8, and all positions are calculated using this number. This may very well be wrong for some cases. I think it is mostly 4 nowadays, but should be configurable.
This was found after reading @larsac07's thesis: http://bora.uib.no/bitstream/handle/1956/12756/144804725.pdf
@larsac07 - if you have more suggestions, please add :)
Yay! Someone read my thesis!
@larsac07 turns out you weren't the only one bothered by the TAB thing, by the way - in the new version it was changed to 1 already :)