Just checked seat reservations for some upcoming flights, and happened to notice the seat map on Expertflyer (seat reviews credited to Seatguru by Tripadviser) said:
"AVERAGE REVIEW. Seat 1A is a standard Club World seat. This seat is usually booked for the captain."

And for good measure, the review of 1B said:
"BE AWARE. Seat 1B is a standard Club World seat. Seat 1A is usually booked for the captain, and the crew's presence around the captain may be bothersome."

I've never noticed this comment before. I've managed to nab 1A myself a couple of times in the past. And I've never noticed a captain (or any other crew member) actually occupying a CW seat on a B767 flight.

Assuming this is just some out-of-date info displayed by SeatGuru - which (for this cabin at least) is pretty useless. They fail to flag 1A and 4K as "Good Seats" and their 'no-step' access.