This is basically me repeating things I think I said here before, but for a good portion of Allen's tenure on P+, they had the clues arranged much differently from how they would be later. If the puzzle were "American Idol," they'd have SEACREST-SINGING-FOX-TELEVISION-COMPETITION, whereas later they'd be reversed. I mean, once you see Seacrest, you might as well guess Idol, and it's a shoe-in on word 2 unless you just never heard of the show.
Then I watched a few episodes from the Steve Allen/Jayne Meadows week of Kennedy's run, and roughly 5 out of 10 puzzles I saw went unsolved. As I recall, the five words didn't really lead you to one solution. Once "Super Password" came along, they started to get really tricky with the puzzles, almost deliberately leading you astray until the 3rd-5th words came in to make the early ones make sense. It was a good idea, but the contestants (and a good chunk of the celebrities) weren't very good at all, and would give great guesses like "JFK" when the word "Kennedy" was up.
-Jason