Good point. I had a good 'smith lighten the DA on a 686, and the thing wouldn't light up more than 2 or 3 rounds in a cylinder (CCI primers!). I basically had the option to go to Federal primers and hope, or go back to something closer to stock on the springs. I chose the latter, and it still groups great when I've practiced -- better than the 2-1/2 lb trigger in my custom 1911 in rapid fire inside of 25 yards. The weight itself is not such an issue. It needs to be smooth, clean, and consistent.
Bit more on that last term. I keep hearing/seeing people stating that you should be "surprised" by your trigger breaking. That statement is simply UNTRUE. You should know when your trigger will "let off". If you don't, you either haven't fired the weapon more than a few rounds, have a mechanically inconsistent trigger, or have no real feel for trigger pressure to begin with. The point is not to "surprise" yourself with the shot, but rather to remain focused on your sight picture and not shift focus to the trigger, abandoning sight alignment before the shot is actually away. Great target shooters can nearly always "call" their shots. THey can tell where the hole should be before they check their spotting scopes because they knew exactly what the sights looked like the instant the shot was fired. They also only add pressure when their sight picture is satisfactory, not at some random moment. Anyway, a good clean, consistent trigger beats a light but "creepy" inconsistent trigger any day!