The bit about wet and dry was supposed to be quoting Danny..!
For all the reasons you said I have and do always prefer FTD....
it would be very unlucky to have 4 bad rounds, but quite possible to have 2 or 3 for various reasons, setup ,tyres, accident etc. but one good clear run could still give a good final position... I think most drivers would prefer that one good run , their maximum potential, to count for final position.
Seems though I may be wrong...