Yep, what he said. When I replaced my cable it only took about 1/3 the pressure. Now that I think about it, it's prolly time to relube.
Which is easier? Six and a half dozen. Replacing means taking it off and putting it on, lubing means standing there and sliding the cable in and out for a bit. Both are easy enough. Personally, unless I saw signs of wear at the cable ends, I'd just lube it to keep up my cheap bastard facade.