This has been touched-on in other posts, but I'd just like to emphasize the point.
Mr. Blumenthal has offered great detail on how he tried to extend the game-- or at least challenge the contestants and the viewers-- by designing the prize lay-out in such a way as to not give too much away, too quickly.
But it should also be pointed out how Mr. Blumenthal used his grid to give away parts of the puzzle ever-so-slowly.
Take, for example, the last puzzle on the NBC run, "You've been more than kind".
http://concentrationphotos.shutterfly.com/pictures/9There's no pay-off at all for turning the numbers 1, 3, 4, 11, 14 (a killer), 17 (another killer), 26, 27, 29 and 30
As for the other trilons:
#2: Head of the bowilng pin. By itself: Could be anything
#5: Oar? Hoe? Wand?
#6: YU. (You won't get "You've" without #7
#7, #8: Part of the pin. Again-- could by anything
#9: The "M":Key reveal
#10: Another piece of a handle. No giveaways
#12: What a tease. a white triangle? Almost mean!
#13: Body of the pin. Alone-- not sure what you'd make of that. You might get the pin with 7, 8, and 13, But I bet most needed #2 as well.
#15: The paddle of the oar: Another key reveal
#16: the top of the "Th+" In lower case, just to confuse, I suspect. Is it a cross and a stick? Without 21, you're lost.
#17: "hen's" head. If you know the game-- you know what this is. Key reveal
#18: Top of the weird "k"- four parallel lines. No help by itself
#20: An apostrophe and the top of the lower-case 'd". Floating lines. No help
#21: "in" without #16... maybe the biggest red herring on the board
#22: Hen's body. Without the head, you might guess another bird, but that may be Mr. Blumenthal's make-up gift for #21
#23: You get the "+", but by itself-- B? R?
#24: The eye. Love the eye. Key reveal
#25: Good chunk there two. nd is pretty clear.
Okay-- forgive me for the over-analysis. The point is, it is clear Mr. Blumenthal put that kind of thought into EVERY puzzle he designed. That's the genius of it all. And all great fun.
Here are some links to the Concentration set model I built, in tribute to Mr. Blumenthal's work and vision.
http://concentrationphotos.shutterfly.com/pictures/9#10http://concentrationphotos.shutterfly.com/pictures/9#11http://concentrationphotos.shutterfly.com/pictures/9#12