As Word of Mouse games seem to go, the shareware only allows a certain number of higher level games before it won't let you play anymore. This number is large enough to make sure that you're thoroughly addicted by the time it runs out.
My Snoodoku ran out last night. Now I'm stuck with "easy." Having just spent an entire week where I did nothing else with my non-work waking hours, this is probably a good thing.
Was it all a colossal waste of time? At the risk of sounding like I'm rationalizing: I would say no, because I learned things. I went from being so utterly clueless that I couldn't even complete a "child" puzzle correctly, to doing "evil" puzzles in as little as 25 minutes. I learned how to look at all Snood possibilities for each box, and then I learned it was faster to look at all box possibilities for each Snood. I learned and invented terms for a number of recurring situations that help winnow them down: singlets, line eliminations, mated pairs, orphans. In my last two allotted evil games, I began noticing some emergent patterning properties, which would probably become more clear if there were 4x4 games (16 possible Snoods in 256 possible boxes) or 5x5 games (25 possible Snoods in 625 possible boxes) - but so far as I know, Sudoku is only ever 3x3.
Were any of the things I learned important?
Well, yes. For the same reasons that IQ tests are based on discerning patterns. For the same reasons that one learns maths more advanced than arithmetic in school, even if one will never use them again. Puzzle games are logic exercises. Ways of thinking learned from puzzle games can be applied elsewhere in arcane, unexpected ways. They can even be the foundations of entire paradigms. ("Life is like a game of Snood because..." etc.)
Also, mental stretching of any kind is always good. The brain is like any other part of the body - use it and become more powerful, or lose it.
Or, in my case since I'm as done with the learning as I can get without paying, and no longer have access to the levels that require thinking, it now becomes one of those mindless things I do with my hands while I'm thinking about other things.