Good question but lots of answers to it.. me personally, I seem to always troll a little faster then everyone else. and the opposite way, I go with and agaisnt the tides.. and I can honestly say I have caught a lot more fish going against the tide then with it. Don't know why that is.. maybe i'm just lucky???

I would suggest watch your lure, plug ect.. and find the speed that really makes that thing work the way you want it.. then keep er at that speed.
dave