Here's another vote for setting the drag rather light, about a quarter to a third of the breaking weight, then using your thumb to adjust it while fighting a fish. Here are two more reasons why...

1. As you have line go in or out of your reel, the spool diameter increases or decreases, respectively. As it decreases, the drag becomes tighter without touching the drag adjustment, and as it increases, it becomes looser. The variability can be removed by adjusting the pressure of your thumb to keep it somewhat consistent.

2. Similar to #1, the more line you have out, the more stretch you have in your line. A drag that may have been set properly for fifty feet of line out may snap your line at the beach when you're just about ready to punch your card. Again, your thumb can be instantly variable.

The unfortunate thing about using your thumb to make up for the variability in spool size and line stretch is that the only real way to learn it is through experience. That said, I think it's worth it anyway. When I'm fishing with newbies I always set their drag rather light and help them use their thumbs when fighting fish. It's a disappointment if a fish comes unbuttoned for a newbie, but if a fish breaks their line, the look on their face says "If I had an ice pick, I'd stick it in your ear right now!".

Oh, BTW, if you set your drag for six pounds with eight pound line, I'm 99.9% sure you'd either break your rod or your line long before the drag would come out, depending on the weight class of your rod. Even a very good knot will reduce your line to about 2/3 to 3/4 of it's breaking strength.

Imagine an average 8# hatchery brat. Would you attempt to lift it straight up out of the water with ten pound test on a rod rated for 8-12 pound test? Only if you want to break your line and/or rod!! As noted above, you'll be very surprised if you set your drag as you usually do and then attach a scale and see where it is. I'd guess the average for 10# line is somewhere around 2-3 pounds.

Fish on...

Todd.