Exactly. Signal strength is not an issue.
Mounting inside would be just fine. You could mount in a foot off the floor if you wanted, and in fact that may work even better, attenuating the more distant sites even more.
If you look at my pics in the yagi thread you will notice the yagi is mounted fairly low on my mast. The only reason it didn't go in the attic was that the mast was just so convenient to mount on.
If I were in an apartment, I would probably mount it near the ceiling, aim it accordingly, and call it good.
An added advantage of having your antenna within easy reach would be that you could easily rotate it to find your "sweet spot".
As well, with a short run any cheap cable would do fine, and you wouldn't need static discharge / lightning protection.