“Diagnosis Murder”: One of the least fashionable of shows finds itself smack in the middle of the trend mall tonight. First off, tonight’s episode of the Dick Van Dyke series (8 p.m., WBBM-Ch. 2) that targets older viewers is part of a crossover with its equally unchic predecessor, “The Promised Land” (7 p.m., WBBM). Crossovers, a kind of cast-sharing plan, are, of course, all the rage among TV series, especially during Sweeps periods, the latest one of which begins today. Sometimes this commingling brings sparks that merit the effort and the publicity; more often, a crossover is a haphazardly tossed together thing, a chef’s salad with both ham and bacon. The second trend on “DM” is the wave of country singers who, apparently beginning to share my dissatisfaction with the ultrabland state of country radio, are suddenly getting work as actors. Like Trisha Yearwood (in next Tuesday’s “JAG”), Jimmie Dale Gilmore, Billy Joe Shaver, Willie Nelson, Lyle Lovett, Reba McEntire, Travis Tritt, Randy Travis, Clint Black and more, Pam Tillis hits the boards, showing up on “Promised Land”/”Diagnosis Murder” as Kate, a con artist trying to re-enter the lives of her husband and teenage daughter. I haven’t seen tonight’s dual episode, but I did watch last week’s “Diagnosis Murder” and found an unsubtle but well done, old-style TV drama that indicted the parsimonious nature of bad HMOs. Elsewhere tonight, Dana Carvey does a very funny, if a tad familiar, guest turn as an egomaniacal fashion designer on “Just Shoot Me” (7:30 p.m., WMAQ-Ch. 5).
