It's always been unfair on the counties whose top players were picked for England at critical times.
In 1979, when Essex won their first title, John Lever was forever being picked for England only to find himself being made 12th man. He was the best English pace bowler in the Championship by far - he took over 50 wickets in June 1979 alone.
Essex won 6 titles in 13 years from 1979, despite the fact that their best players (Gooch, Fletcher, Pringle, Foster, Border, Waugh...) were often on test match duty. The one world-class player who wasn't was McEwan. One of the best attacking batsmen in the world and he never played a test because he was South African.
I have to say that in the last round of matches, when Somerset came severely unstuck against Hampshire and Essex won comfortably against someone else, the matter was in Somerset's hands. If they had beaten Hants in that low-scoring game they would be top of the table now and the wet weather would be their friend.