There are some playwrights who really should be novelists, and William Hauptman is one of them. Two of his one-act plays, "Comanche Cafe" and "Domino Courts," currently being given respectable productions at the Touchstone Theater Co. in Arlington, present the curious case of a writer caught in the wrong format.

Both are set in Oklahoma of the 1930s which, we are told--but not shown--is a dustbowl of depression. Hauptman's characters are waitresses and failed bank robbers with Hollywood-style ambitions, plain folks ineffectually resisting their fate. The trouble is that these plain folks talk like back-porch poets and philosophers, waxing eloquent about dreams and plans with words that seem alien to their characters.

"Comanche Cafe" is a fragment rather than a play, a 20-minute conversation between a young waitress who dreams of leaving Oklahoma for anywhere else and an older waitress who has settled for a circumscribed life and says "every place is the same."

In the second play, the young waitress reappears, married to a man who was once a bank robber and now does nothing. The man's former partner arrives with his wife for a reunion, and as the evening progresses the fac,ades each has Theater constructed to impress the other crumble. As they reveal their pathetic, failed lives, their behavior swerves into the absurd, with one man becoming a gibbering fool, afraid of fire and dogs, hiding under a bed.

The women are similarly ineffectual, endlessly complaining and confused but willingly trapped by their men. After a while, Hauptman's characters seem to be whining and falling apart because of banal weakness, rather than anything more dramatically interesting.

The theater is simply but attractively housed in a former gift shop in the Parkington shopping center, one of the last human-sized shopping malls, soon to be replaced by one of those massive "gallerias." The plain and simple set, framed with a massive backdrop of a road heading into the horizon, is an example of how small theaters can use their limited resources effectively, and director Gillian Drake has orchestrated the proceedings with appropriate economy.

The performers are somehow restricted by the poetic language. Marcia Gay Harden as the young waitress has an appealing quality of pouty expectation, although she occasionally turns Ronnie into a cliche'd hick. The others--Gerry Paone, William de Rham, Catherine Ann Beals and Ida Eustis--struggle to make their characters more than two-dimensional but have a hard time surmounting the difficulties the author has placed in their paths.

COMANCHE CAFE and DOMINO COURTS, by William Hauptman; directed by Gillian Drake; lighting by Steven Holliday; set by Henry Shaffer and Jacqueline Shaffer; costumes by Wendy Dewey; with Marcia Gay Harden, Ida Eustis, Gerry Paone, William de Rham, and Catherine Ann Beals.

At the Touchstone Theater Co. through July 18.