Trigger weight is one of 4 elements that make or break the utility of a trigger. IMHO, smoothness, creep, and over travel are more important that weight alone, and nothing is worse than a long, creepy, gritty, light trigger, but one can effectively use a rifle with a "glass rod" trigger that brakes at 5 pounds. If you're shooting a rifle with a single stage trigger, the movement of the trigger should be imperceptible, yet it must move to release the sear. A two stage trigger is best when you can feel the end of the take-up, and from that point onward has the feel of a single stage trigger. While good shooting can be accomplished with rifles having poor triggers, they impose an unnecessary hardship. The quality of the trigger, more than any other element of the rifle, allows the shooter to appreciate the degree of accuracy that his rifle has to offer. No element of the rifle is more harmful to a shooter's confidence than a poor trigger.
How light should a trigger be? It depends on how the rifle is used, and it depends on the conditions it is used under. A big game rifle that has a trigger so light that it breaks before your finger contact can be felt, it is inappropriate, for that purpose. The trigger on a benchrest rifle must break without any disturbance to the rifle, so a trigger whose wight is measured in ounces, rather than pounds, is appropriate. I don't want the trigger on my .458 to be as light as the trigger on my .223, or my 20 pound .308 target rifle. But, I want to be able to feel my finger contact the triggers on all of my rifles, and I want the rifle to fire when I will it to, regardless of how powerful it is.
Different people use their triggers in different ways. If you push your finger into the trigger guard and contact the trigger with the second pad of your finger, your mechanical advantage is greater than it would be if you contact the trigger with the first pad of your finger. You would find that most of my rifle triggers were set lighter than you'd be comfortable with. Yet if I encounter a rifle with a particularly difficult trigger, I'll use the second pad of my finger to gain mechanical advantage. An unintended consequence of using the second pad of the finger to engage the trigger is that it causes the finger to contact the side of the rifle, and the longer and more difficult the trigger is, the more likely it is that this contact will disturb your aim just as the rifle fires. Dry firing will confirm how much. If the trigger is too heavy for you though, using the first pad of your finger might well induce shake to the rifle, and in extreme examples, cause pain in your hand. Clearly these circumstances are worse than the disturbance created by "dragging wood."