Uncursed - Rolls the usual calculation an extra time and chooses the most favourable result.
Blessed - Rolls the usual calculation two extra times and chooses the most favourable result.
Cursed - Rolls the usual calculation one extra time and chooses the least favourable result.
In other words you'd have to drop projectile/fail to return projectile three times in a row without gloves to equivalently fail while wearing them blessed.