Re: Drag on a fly reel
I doubt you will ever see the drag engage while you are fishing for bluegill and small largemouth (unless they strike right at the peak of your cast length.
I use a 6wt rod, 20lb mono leader, and 12lb mono tippet for these same situations, because theres a lot of vegetation that I need to yank my bass out of. I pretty much never worry about breaking off. Even if a fish does get on the reel, I never adjust the drag (which is set to very low) and simply hold the line to create drag when I need to).
I think drag is really all about what tipper sizes you are using, how big the fish are, and what tendency they have to run. Bass typically do not run, then tend to hunker down and head for vegetation. Bluegill make nice little runs, but are rarely large enough to warrant a second thought about giving them line (if you are using leaders/tipper designed for bass). Trout require small leaders and tippets and letting them play on the reel and drag may be a good thing. A nice smooth drag will protect a light tipper as it applies even resistance. This being said, some trout just like to splash around a bit and can be effectively fought by holding the line.
Really, its all preference for the large part I think. Sometimes I let fish on the real just for fun. Most times I just hold the line and pull them in, I think it's more fun that way. More fish-fisherman connection.