So in theory:
Batch 1
Titan = 2500 * 300 = 750gh
Mini = 1200 * 150 = 180gh
Subtotal: 930gh
20% overclock: 186gh
Potential: 1.1TH

Batch 2
Titan = 2500 * 400 = 1000gh
Mini = 1200 * 200 = 240gh
Subtotal: 1240gh
20% overclock: 248gh
Potential: 1.48TH