Unfortunately it's pretty common for shots at contact size to look in focus and/or sharp when they aren't. Only a loupe confirms if it's proper - and if the contacts weren't done direct to paper then everything has a general light softness to it. This is pretty much why I go through the trouble of glass on naked negs the first time. I expect and want the contact sheets to last a long time.
Originally Posted by travelingman
Aside from individual negatives, the contact sheets can be a chronicle of one's photographic approach, progress, and experiences. Sometimes it isn't even necessary to look at prints - you can look at contact sheet after contact sheet and feel a story or connected theme.
Stop worrying about grain, resolution, sharpness, and everything else that doesn't have a damn thing to do with substance.