The Write Stuff : The guys behind ‘Which End’s Up?’ are a fount of good ideas, but their performance feels like a rough draft.

John Moody and Doug Cox call their evening of comedy skits and improv at the Lionstar Theatre “Which End’s Up?”--a good question, they point out, after the big quake.

The answer, as far their act is concerned, is the writing end. With most comedy sketch acts, including their alma mater, the Groundlings, it’s the reverse, with performing far ahead of the writing. In this respect, “Which End’s Up?” turns things around.

When it works, comedy theater balances writing and acting in a way no other form does. As a comic told me, the delivery needs the line, and the line needs the delivery. Which is largely the reason good comedy theater is so rare.

That Moody and Cox, under Glen Chin’s direction, tilt the balance to the other side doesn’t make their work better than the competition. It just makes us note how their lines need the delivery.

We like, for instance, their setup with Moody’s lonely telecommuter who badgers Cox’s door-to-door Jehovah’s Witness proselytizer, but we don’t believe the actors for a moment. Another sketch, with Cox as the jilted sensitive vegan boyfriend moving out and running into Moody as the new, gun-toting boyfriend, is less sharply scripted, but it could have been pumped up in the playing. Here, it looks and sounds tired.

Both of these guys are really short-order players--the quicker the serving, the hotter. “Big Top Burger Drive-In,” which plays on fast-food clerks’ irritating habit of suggesting dishes you don’t want, is one skit that’s over before you realize it. Another nearly works as silent-film comedy, in which Moody’s angry acupuncturist tortures patient Cox, who’s having an affair with Moody’s wife. It’s cruel but compact, and it knows when to end.

A lot of scenes don’t, alas, which is another problem with most sketch comedy. The worst sinner is unfortunately the closer, a belabored set of improv scenes about an air-conditioning shop owner with a spastic son. Granted, Cox and Moody must play with audience suggestions in this situation--thus robbing themselves of their writing strength--but when the suggestions are this bad, the duo is visibly stuck in place.

It’s not a good way to end a show, and on Saturday, Cox and Moody appeared to be glad to get out alive. For the next show, they might look to that TV monitor hovering above their heads on the Lionstar stage. Their TV-related bits, such as a running stream of political campaign ad spoofs, contain enough visual and topical spice to suggest that this is a user-friendly medium for this comic pair. Just as long, that is, as the tube doesn’t consume them wholesale.

Where and When What: “Which End’s Up?” Location: Lionstar Theatre, 12655 Ventura Blvd., Studio City. Hours: 8 p.m. Fridays and Saturdays. Ends March 5. Price: $12.50. Call: (818) 955-8647.