Unless you’re a really dedicated Idina Menzel fan, you can take a pass on this high-concept musical by Tom Kitt and Brian Yorkey. Menzel plays Elizabeth, a recently divorced almost-40 city planner returning to NYC after 12 years in Phoenix. She seems more interested in dwelling on past choices than in moving ahead with her life. A seemingly trivial decision about which friend to hang out with after an encounter in Madison Square Park leads her down two different paths, one as Beth, more interested in her career than her personal life and the other as Liz, who values love above career. Following her down these two different roads sounds more interesting than it turns out to be. Neither story is particularly compelling and the alternation between them is both confusing and unproductive. The people who surround Liz/Beth are right out of the cliche book — Lucas (Anthony Rapp), a mostly gay housing activist, Kate (LaChanze), a sassy black kindergarten teacher, Josh (James Snyder), a noble doctor just returned from military service; Anne (Jenn Colella) and David (Jason Tam), two cardboard characters to provide romantic interest for Kate and Lucas, and Beth’s boss and mentor Stephen (Jerry Dixon). Mark Wendland has designed an attractive, flexible set complete with turntable and huge overhead mirror. Kenneth Posner’s lighting design features a glowing backdrop of changing colors, some of them quite bilious. Emily Rebholz’s costumes do not distract. Michael Greif keeps things both stories moving with only occasional confusing moments. And then there’s the music, none of which I could hum if my life depended on it, and the lyrics, which rarely rise above the humdrum. Since I am old-fashioned enough to think that the music is the main point of a musical, I find the show wanting at its core. Menzel is a commanding performer, but she can’t elevate mediocre material. Running time: 2 hours 45 minutes, including intermission.