Roof Ventilation

I have just had my roof retiled, this included the replacement of the roofing under-tile membrane replaced. The original membrane was of the unbreathable bitumen type whereas the replacement membrane is of the Modern Breathable type recommended by my reputable highly recommended roofing contractor. On completion I noticed there were no roof tile vents installed. I discussed this with by roofing contractor and he said that they were not required as the roofing membrane is of the Breathable type and as such extra ventilation is unnecessary and indeed not recommended.
Is this advice correct, it seems OK to me but I am ignorant to such construction details although I have notices on all new developments going on around me, Breathable membrane material is being used but the roofing contractors also install roof tile ventilation.
Can anyone advice me as to the correct acceptable installation.

Yeah its OK.

Thanks Frutbunn, that comes somewhat as a relief, I didn't want a confrontation with my roofing contractoe who has been excellent throughout the re-roofing work.

The roof vent tiles may well be for bathroom fans, or soil stacks.