Given how unpopular Ms. Rohm was with the "real" fans, it would not seem so, however:
One thing that many who hated Ms. Rohm when she was on "Law & Order" as the Assistant DA may not have realized was the show's highest ratings occured AFTER she replaced Angie Harmon to start the 12th season of the show in the 2001-'02 TV season. While the ratings have declined sharply since she left, and some of that can be attributed to writing, perhaps it also could be attributed to when Ms. Rohm left, so did many fans of "Buffy The Vampire Slayer" and "Angel" who came over to "L & O" when she did specifically because she was in the cast.
It may sound ludicrous, except that even though both "Buffy" and "Angel" are no longer on the air, both shows still apparently have rabid fan bases who still heavily discuss the show. It may have been that those viewers did leave with Ms. Rohm and caused a "tilt" in the original show's ratings.