It's important that the square part of the shaft, where the center part of the clutch slides sideways, does not corrode (from being dry) or gum up (from being oiled). My preference would be to keep it clean, and lubricate it from time to time by spraying it with Drislide or something similar: a hydrocarbon carrier that takes some graphite or molybdenum disulphide to where it is needed, then dries up in a few seconds, so only that powder is left. When the clutch plates wear to the point where the shim stack needs to be adjusted, you have to pull the shaft out anyway, so you then rub the square part of the shaft clean, and re-coat it with graphite.
I think what you have done will leave the shaft wet with oil, which will protect it from rust but will trap dirt, and turn into a sort of valve grinding paste. In other words it isn't a disaster, but in my opinion it isn't the best solution.
