G3 blind arcs and concentrated turret firepower

Was the G3's X turret blind over only angles where other British ships also had limited fire?

The restrictions were real. A triple turret concentrated enough firepower that the uncovered stern sector remained a serious design penalty.

The stated firing restrictions left the G3 with no main guns covering some angles directly astern. Other British capital ships might bring only two guns to bear there, but those two guns still provided some fire. Triple mounts changed the balance because each turret concentrated more of the total battery than a twin mount. Stronger fire on other bearings therefore came with a complete blind sector astern. The G3 still emerges as a strong paper design despite that criticism, and its large hull remains especially attractive for carrier conversion.