I have only seen stiff chains from non-use, Like I said I have only lubes mine a couple times in 15,000 miles and it moves just fine , as seen when I adjust it. Has nothing to do with the way the bike performs unless it breaks or you let it sit and rust. It should be cleaned and lubed to reduce wear of the rollers and sprockets. If the O or X rings are not damaged they keep the lube out just as well as they keep it in so there is no replentishing of lube inside the links it will however help keep them in good shape on the outer side where they rub on the out plate of each link. The amount of energy lost to heat would be miniscule and unnoticeable to the rider. All this being said it is still a good idea to lube your chain, it does reduce wear and friction except in the case where the lube is allowed to gather too much abrasive crud and thus speeding up wear.
