Moderation is not the chosen path of many artists, but it is pianist Thomas Flagg's, and in pursuing it, he speaks strongly and eloquently.

His program at the National Gallery last night allowed him to explore a variety of romantic sonorities and to enjoy the sensual breadth of some of Schubert's and Chopin's most lyrical melodies. Prokofiev's Sonata No. 7 was fertile ground for a bout with aggressively rhythmic material; Beethoven's Sonata Opus 10 No. 3 and three pieces by Mark Fax required drier, more calculated clarity.

Flagg, who is dean of the College of Fine Arts at Howard University, met each of these works on its own terms but stopped short of any hint of overstatement. In the Schubert G-flat Major "Impromptu" and the Chopin "Barcarolle," the melody was clearly in the foreground and beautifully balanced with the accompaniment, but there was no attempt to transcend the legato limitations of the piano, nor any particular effort to explore philosophical dimensions of the music.

The pieces by Fax -- nice, contrapuntal, well-written works -- were played with enormous care and concentration, but remained entirely within their unassuming proportions. The Prokofiev, powerful and compelling, retained a feeling of strong control and restraint. Only the Beethoven seemed unresolved. Here a greater variety of tempos, a little more rhythmic flexibility and increased attention to the shape of the ends of phrases might have made the performance more convincing.