Interesting math. You've done much better than I did with my 1 BTC puchase. Did you have any converted hardware?
I have sold off most of my Primes, have 6 left, purchased same stalkers because I couldn't withdraw my last $60

. I have barely broken even, give or take a few bucks. I did some experiments that lost me money though, e.g. with Genesis, with the Market etc.
how did he turn 1.6btc into 1.993btc mining....? is the difference the mining revenue i.e 0.33btc?
can you post what you had in hashlets e.g 1.6btc bought 15 primes @ 37$ each and mined zen for 10 days with each prime giving me 0.0006 btc a day.
this would be interesting to see
I went in on a group buy for a Vaultbreaker (bought 60MH's worth) for the 1.6 BTC. These were converted to 60MH/s of Primes. I got my Hashlets on day 1. In the beginning Zenpool was actually pretty profitable and I was able to ROI pretty quickly. Then shortly after that it really slowed down (the rate nearly halved) and I switched to earning HashPoints. That's how I earned the 1.993 BTC from mining. I was also pretty vigilant at using whatever boosts they were providing as efficiently as possible.
60 MH/s at Zenpool earning 0.0006 and then double dipped at LTCPool earning 0.0006 adds up to 0.072 BTC per day. Things really did used to be a lot better.
When the Hashpoint mining stuff started, I bought 1.5BTC worth of Zens. Used them to mine Hashpoints for a few weeks, then sold then in the market and got back nearly all of the 1.5BTC I used to buy them.