Yes, and that rulebook is written by GW.
This forum alone proves that they do not write clear, concise rules that always have a easy conclusion.
I would much rather have a list of rulings spelled out ahead of time than deal with a local groups 'house rules' which is what you are describing.
There are several grey areas in the rules, even people of good will can and do disagree on these.
The group that uses the INAT still has the advantage in that there are no surprises.