I've definitely noticed a change in 'feel' as you pass through and in & out of eddies in the presence of strong currents, but through-the-water speed is what it is, I don't think it should change the helm's feel if it's a consistent current.
However truly consistent current is pretty rare in our experience.. any time we're in significant current (say over 2 knots) there seems to always be random turbulence so I suspect what you're feeling would be the ebb and flow of eddies on the rudder.
1984 Fast/Nicholson 345 "FastForward"
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)