Puzzle 7 illustrates a position where it is imperative to block as many bingos as possible, as you will be unable to outrun any bingo.  While some plays look tempting to leave row A plays with the Q, these plays don’t outscore many bingos.  The best way to win is to make a blocking play that still scores enough points and doesn’t leave open enough scoring options to outscore you, even if you draw badly.  The best play that accomplishes this is LEUCONs b7 (14), scoring enough to block columns b through c as well as neutralizing row 13 and scoring enough to outrun your opponent even with a 3 vowel draw.