This is not a direct answer, but in a way in the 1st halves of the last two seasons.
Gaffney receptions:
2003 1st half--24, 2nd half--10
2004 1st half--28, 2nd half so far--5
Carr has quite the 1st and 2nd half of the season split going as well:
2003
1st half--59% comp %, 6 TD's, 8 INT's, 75.2 QB rating
2nd half--49% comp %, 3 TD's, 5 INT's, 58 QB rating
2004
1st half--64% comp %, 9 TD's, 5 INT's, 104.8 QB rating, 2.5 sacks per game
2nd half--58.7% comp %, 4 TD's, 7 INT's, 66.5 QB rating, 3.4 sacks per game
Now after last season I thought Carr's progress should be judged only on his 1st half last year because he got injured so the 2nd half "didn't really count." Seems to have had quite the slide for the 2nd half this year as well without any acknowledged injury. He has had more pressure but a drop from 104.8 to 66.5?