I think your missing the point. At present a tank or anti-tank gun for example set up in a town is always going to have an enemy claiming it as "in the open" if it positions itself to be able to fire (i.e. with its nose poking round a corner of a building) I'd like to say that we were fair enough in our games to give the target the benefit of the doubt of it being partially concealed BUT WE DON'T. (This is borne out of observation of what must now be hundreds of games that we have played in the last 5-6 years).

So let's not dismiss the idea of using tiles to delineate a built up area since troops and vehicles thus placed in the tiles are in cover, albeit not behind a building but a substantial pile of debris, while those on marked roads are themselves more difficult to spot from a far (as when parked along side a building) but not necessarily gaining any protection from fire.

I like this idea so much I will be implementing it together with the crawling rule in my Sicily bash, which incidentally we could run this weekend if people (and figures) are available.