This strip, if your only experience with Peanuts is the later era, is striking in how it treats Snoopy like just a dog. No abundant imagination, no literary pretensions, no "world famous" anything, no Woodstock, no "Happiness is" smarm, no walking on his back legs, and no thought bubbles.
This strip is, I think, padded out a bit. Particularly Schroeder's line "We can't.. we just can't" and Lucy's "You don't understand," both of which seem kind of hollow; the only reason they don't just say "We can't because he's sitting in the sprinkler" is because that would spoil the reveal. Probably panels seven and eight could be removed and the rest rearranged to make the point in fewer panels. Remove the top line of three panels and just four remain, exactly the length of a classic Peanuts daily strip.
Still not a bad strip though. It is a funny joke in the end. Snoopy's smiling expression sells it for me.
