So before the comment, I have to say that I totally agree with the concept that a Bitcoin is always a Bitcoin regardless of the current price, but now that you have been very organised on your calculations, why dont you include BTC/USD rates as well? I will be a lot more realistic and dont think you really "profit" taking this into account!
RD
Read my response to elasticband, I think it also answers your point :-)
I know not everybody sees that way - consider each investment per si - but that's how I stand.
Let me give you another example, without BTC:
You live in Europe and work with EUR.
You buy some stock in NYSE in USD.
The stock goes up by 10% over a year and, in the same time period, USD drops 12% in relation to EUR.
Was that stock a good investment? In terms of the stocks' valuation, it was a hell of an opportunity that paid out! 10% in a year is a very sweet deal.
Was the USD purchased to buy the stock a good investment? Hell, no. I lost 12% in a year.
If you do the math, you can see that the stock's valuation in EUR is, at the end of the period, just 92,21 % of the initial investment in EUR - I'm loosing a net worth of 7,79%. A pretty lousy deal, by any standards :-)
This little mockup shows exactly what you feel about PBmining: That it's risky.
However, it shouldn't take this much to understand that to make investments on something that can have daily fluctuations of over 5%, it's traded 24/7 and a steady decline of over 50% in 6 months ... is a very risky business!