Hi Jim,
This can work as there is a very nice schedule for the first 10 rounds as follows:
foursome threesome bye
( 8 2 1 5) ( 7 3 9) (4 6 10)
( 9 3 2 1) ( 8 4 10) (5 7 6)
(10 4 3 2) ( 9 5 6) (1 8 7)
( 6 5 4 3) (10 1 7) (2 9 8)
( 7 1 5 4) ( 6 2 8) (3 10 9)
( 2 10 7 6) ( 1 8 3) (4 5 9)
( 3 6 8 7) ( 2 9 4) (5 1 10)
( 4 7 9 8) ( 3 10 5) (1 2 6)
( 5 8 10 9) ( 4 6 1) (2 3 7)
( 1 9 6 10) ( 5 7 2) (3 4 8)
Notice that each player appears once in each of the first 7 columns, so one player gets 4 foursomes, 3 threesomes and 3 byes. So one player has (4*3) + (3*2) = 18 opponents over the course of 7 games. Above the schedule is arranged so that each player plays against all 9 possible opponents exactly twice each.
If you want to play the 8th game then you can choose any assignment of the 10 players to a foursome and two threesomes for the last two nights. But if you keep score for the first ten weeks, then you could choose to make the 8th game a play off for a prize.
Hope that helps,
Ian.