I'm correct in my math. 60 servers x 16 cores x 2.5Mh = ....
I was being conservative at 2,000Mh. It's actually a bit higher.
I run the ltc.kattare.com pool, I have a semi-decent idea how it all works.

Looks like I have reproduced the issue with cpuminer on testnet. I will continue to look into the cause in the next few days and will update if I have more discoveries.