I think it actually depends on the saddle to bar height difference of the bike in question (as well as rider preference).
For example I own two bikes with Brooks saddles:
My road bike has a Swift, my bars are slightly lower than the saddle and I find it extremely comfortable with the saddle ever so slightly nose down, with the saddle rails bang on level.
My 50 year old Pashley Post bike shopper is a sit up and beg type thing with the bars higher than the saddle. This has the saddle slightly tilted up at the nose.
I think it actually depends on the saddle to bar height difference of the bike in question (as well as rider preference).
For example I own two bikes with Brooks saddles:
My road bike has a Swift, my bars are slightly lower than the saddle and I find it extremely comfortable with the saddle ever so slightly nose down, with the saddle rails bang on level.
My 50 year old Pashley Post bike shopper is a sit up and beg type thing with the bars higher than the saddle. This has the saddle slightly tilted up at the nose.
#csb