MM -
I fully agree that a "clean & relatively light trigger" (what I would call a "decent" trigger) beats the heck out of a crappy one when it comes to precision shooting. That's why I've replaced a couple and reworked many (my Timney came pre-installed on a naked Interarms Mark X action that became my 6.5-06AI).
Tried to clean up a crappy, standard AR trigger (against the advice of rost495 and others) and ended up with a smooth trigger that fired twice - once on the backstroke and once on the reset. Now I see commercial triggers that do that, so maybe I was just ahead of the times.
That AR got the Ruger trigger, which cut the group size considerably.