From CS25:
(4) The landing must be made without excessive vertical acceleration, tendency to bounce, nose over or ground loop.
[Amdt. No.:25/3]
(5) The landings may not exceptional piloting skill or alertness.
I´m aware of the fact that 4 might - in some cases - contradict 5. How "they" do that in real life should a test pilot be able to answer.
AFAIK - FWIW - the landing field dist tests are done with brakes and tires worn to the limit.
Although not really part of this discussion, some dudes are not aware that Vref might not be VSO x 1,3 on their type. Some airplane use VSO x 1,23 these days. (E.G. Citation Sovereign) The lesser margin one can will feel in X-winds and or steeper approaches...running out of elevator before touching down happens on the Sov if you´re not careful...
Back to CHR:
WHICH manual ? If it is the manual of the airplane (AFM) then you determine what factor you need to use (1,67 as a comm operator or 1.0 for private ops) and then you factor that with 1,15 - which equals 1,92 for the commercial dudes.
Some non commercial operators use factors such as 1,25 for dry and 1,44 for wet runways (thats what we do).