We took a "lunch break" at 4 and returned to grout the last 2 rows of tiles. Suz came in to aid in the final cleaning(s). Here we are happy to quit for the day (at 8:30PM):
For the last 2 passes we used a grout haze remover (from Lowe's) diluted in water in various ratios. We'll be getting some more of that to go over the tiles one more time in a stronger solution, but they still lookk great! The grout is actually "London Fog" grey and dried a bit lighter than expected, but will still go a long way to hiding dirt.