Sure. The idea here is to use the rheostat to zero in on a figure, and then replace it with a non-inductive fixed resistor. I'm assuming that the series inductance won't make enough of a difference in the frequency response to render the results useless, but without running the numbers (or trying it) I can't be absolutely sure of that.
Wslam, a lot of people recommend the Duelund resistors. Whether they actually make an audible improvement over run-of-the-mill wirewounds, I don't know.