Your so right there is total confusion about this.
It's widely accepted that if your living in a flat and there is another flat above you then you have to use Fire proof fitting or fit a fire hood. By cutting the ceiling you are deemed to have lessened the fire barrier and therfore need to fire proof. Often some building controls also insist that you fit the hoods even if you have fire proof fittings, as they then ensure sound proofing.
In your single dwelling then most cases fitting of non fire proof downlighters is done without further protection. Though the ESC advises that if the ceiling is the sole means of fire repression, then it is advisable to fit hoods.
It also I believe that like the height of sockets and switches, you can not fit non fire proof downlighters in new builds, I may be wrong here, and if i'am then I apologise. Though you still can in existing properties.
IMO I would fit the hoods. They are only about 7-8 pounds each and they will give you peace of mind.