leader length

I'm sure this has been addressed numerous times but I'm curious what everyone's opinion is on leader length when drifting. I lost a hook and float the other day and just retied onto the 7 or 8 inches that I had left. I don't remember if that rod caught any more fish that day. I was wondering what seems to be the ideal length and is it affected by drift speed at all. Also, has anyone ever done a real test on this and compared different lengths. I sometimes see blues holding 3 or 4 feet off the bottom on my graph and wonder if I would get more hook ups with a 4 or 5 foot leader. I know they'll move up or down to grab a bait but I wonder if it matters.

Was waiting to see what others said here...

Early last summer, I was catching eaters pretty good one day, and had a couple of rods that seemed to be catching more than others. Was running 2 small boards and 3 rods behind the boat, fanned out. But the 3 middle were pretty close in truth. One of the boards and one of the middle rods had about 12-15" leader with float half way. Did not seem to make a difference if I put fresh cut shad or chicken on them, those two rods were hot. I looked later, and 2 of the other rods had about 30-36" and last was about 24" leaders. All had floats about half way. Was in pretty shallow - 8-12' .

That was just a one day observation...

So my thought is that it probably does matter, but I would be willing to bet that it would change day to day. I think putting it right in their face would be a little better than making them move for it? I keep several rigs tied up, so if I get broke off, can quickly get that rod back ready for action. Keep several different lengths ready but have not had another day that one leader length was enough to make me change things over.

Just more parts of the game to figure out!

Ken