YA
Worth 5 points before any premium square, and the 12th highest-scoring of 96 — tied with 21 others.
YA extends into 9 three-letter words, which is the 43rd least extendable of 96 — tied with 8 others. That is the number worth memorising: a two-letter word is a place to put tiles, but a well-hooked one is a place to put them where the board stays open.
Every hook
- P→PYA
- R→RYA
- H→YAH
- K→YAK
- M→YAM
- P→YAP
- R→YAR
- W→YAW
- Y→YAY
Not all of them are equally reachable, which a bare count of 9 hides. YA hooks on 7 distinct letters, and the ones you are likeliest to be holding are R (36% of opening racks), P (14% of opening racks) and H (14% of opening racks). The rarest is K, at 7%.
How often you can actually play it
Out of an opening rack, 6.06% of the time you hold the letters for YA outright, the 44th least likely of 96 — tied with 15 others. Counting a blank as whichever letter is missing lifts that to 12.69%, though spending one of the two blanks on a two-letter word is rarely the play. Exact hypergeometrics over the 100-tile bag, not a simulation.
It reverses
YA backwards is AY, which is also good. That is how most of this list is actually learned — 46 of the 96 come in reversible pairs, so knowing one gets you the other free.