No offence here! Finally is just a question how they dice the wafers. Maybe it would be even wise, to have 4 dies 25 GH/s each in Multi-Chip-Package. But as you said, in sum they probably will have 100 GH/s per 120mm2.

Funny detail, the minimum count of wafers one can order at a foundry is 25 (1 lot)!

It's really a good question, why invest another $1.5M - $2M for a new 28nm full mask set for gen 2 ASIC if you dominate the market with gen 1?