I haven't seen this Peanuts strip in quite some time. It's one of my favorites of the yearly football-kicking strips, which are sort of Schulz's equivalent of Road Runner cartoons -- a rigid formula, an ending that is known to us in advance, and the fun is in wondering how he's going to get us to that ending this year. By 1970, when this strip ran, Schulz had already sort of given up pretending that Lucy could plausibly trick Charlie Brown into trying again; instead he just keeps trying because, well, that's his fate.
Of the strips where Lucy actually tricks Charlie Brown into trying to kick the ball, my favorite, due to law-school indoctrination, is the strip where she gives him a "signed document" promising that she will not pull the ball away this year. "If you've got a signed document," Charlie Brown reasons, "you can't go wrong." Only in the last panel does Lucy point out: "Peculiar thing about this document -- it was never notarized."