No matter what the reasoning for leaving ventilation off it is not correct. Any non vented roof is going to heat up and the shingles will burn off much quicker and by heating up it is nothing but a sucker for cooling efficiency.

I for one will write it up every time.

As far as calling for every 150 square feet requiring 1 squre foot of ventilation I don't read that just because it is under 150 square feet it doesn't need any. I see this all the time.

Ted