Yellow Flag (Solution)

by Derek Kisman, based on an idea by Amos Eshel

Here is an unordered list of answers to the twenty round puzzles, for reference. The colors identify which puzzle answer this is (e.g. DAMP is the answer to the red/green edge cubelet).
        RYB   SHLEP
        RY    EXTANT
        RYG   DEDITION
        RG    DAMP
        RWG   BOIL
        RW    UNARY
        RWB   CONTIGUOUS
        RB    BASSIST
        YB    SLAUGHTER
        YG    BEER CHUGGING
        WG    EDITH PIAF
        WB    CREAM OF TARTAR
        OYB   ARMORED RECON
        OY    HYPAPANTE
        OYG   COMMEMORATIVE BATS
        OG    DERRICK TRUCK
        OWG   BROWN ROT
        OW    ATTORNEYS GENERAL
        OWB   SACROSANCT
        OB    IMPROMPTU
    

At each position 1-9 of these answers (ignoring spaces), a single letter is repeated across two answers (e.g. there are two words that start with S, two that have second letter E, etc). These letters additionally spell out SEMAPHORE. Forming a semaphore flag by the two positions the answers are in (orientation is provided by red being on the ‘north’ side), and reading in the order of SEMAPHORE spells out the answer, WONDERING.

  NW   DEDITION
  N    EXTANT
  NE   SHLEP
  E    SLAUGHTER
  SE   ARMOREDRECON
  S    HYPAPANTE
  SW   COMMEMORATIVEBATS
  W    BEERCHUGGING
  S NE/E    W
  E NW/W    O
  M SE/SW   N
  A N/S     D
  P NE/S    E
  H E/W     R
  O NW/SW   I
  R SE/SW   N
  E SE/S    G