Warners set meets mostly parallel at the hammer sear interface.
Many do not. P35s actually (frequently) need to "cock" the hammer a little to fire. This is because the angle on the hammer is such that it must move rearwards a little prior to firing. The opposite problem causes hammer follow.
Yea Bill nailed it. For a excellent read on 1911 trigger jobs check out this thread:
http://www.1911pro.com/forum/viewtopic.php?f=7&t=277
If I'm not mistaken Chuck puts forth the idea for the true radius sear in there some where. This thread is mostly about the 1911 but has some hi-power info in it.
Like I said, a long dark hole.
Ugh, the obsession with positive sear engagement at some manufacturers to make sure they can pass ridiculous "drop it out of a helicopter" tests. Have you watched the hammer on a stock CZ-75 in SA mode? It visibly moves a reasonable fraction of an inch to the rear before the sear finally manages to crawl out from under engagement...