Every piston comes to TDC twice. 1) to compress the gas and fire the charge. Then on the next revolution, 2) to push out the exhaust. The term TDC, as commonly used, is #1. When you're setting a distributor and timing an engine, you have to get the #1 cylinder to TDC on the compression stroke. If you use the "wrong TDC" as you put it, the engine won't run.

If you take out all the spark plugs and put a wrench on the damper bolt, you shouldn't have any problem turning the engine with one hand while you have your finger over the spark plug hole.