I have talked to guys running the Aztec track cleaning cars made in Carson City, Nevada, and they have reported using the cars one time to clean track and having it stay clean as long as they keep running trains. The problem with dirty track and wheels are bad with dc where the motor in the engine is powered from electricity in the rails. With dcc the problem is made greater by the need to run high frequency rf signals through those same rails to give the engine control commands. It is especially problematic in switching where you are operating at slow speeds and need to stop precisely to keep from overshooting your siding or drop point. At the club we had some difficulty with dirty track and wheels and tried switching moves. We found that the locomotives would miss commands to stop, miss commands to change speeds, and sometimes miss commands to start. With dc you don't have that problem, the locomotives just won't run when they hit dirty track. There was an outfit that used to make a capacitor discharge system that would keep the train running over dirty track. I used to see them demonstrate the product at train shows by having a piece of milled wooden track with wooden roadbed and wooden rails about 9 inches long or so in the middle of a circle of track. They would then run the locomotive around the circle and show that it didn't even change speed when going over the wooden rails. With dcc, there are more problems than just getting the locomotive to run over dirty sections of track, so I don't know if that company is still in business or if they still make that product. With Squidbait's admonition in mind, it will work better to build your bench work in sections and lay track in sections then test run some trains through it before you go on to build the next section. If you aim to build it all, and then test run it, you may find the problems overwhelming or even a problem severe enough that it would require ripping out the layout and starting over.