Eclipsed **** Blackbird **1/2
By: David Sheward Sexual exploitation is a rare subject on Broadway, but two new productions are addressing this explosive topic. Both have honorable intentions, but only one totally succeeds while the other suffers from a strained starring performance. Danai Gurira's Eclipsed is stunning in its total approach to the sensitive topic, allowing humor to mix with pathos, while the brutal impact of David Harrower's Black…