So the point many people are trying to make is not that they would have made more USD by buying BTC directly instead of a BFL miner but that they would have more BTC plain and simple. The exchange rate doesn't matter and your point is moot.
/school
but you are living in a vacuum of your own making.. you are surrounded by new entrants playing a different game
the 'ROI's are not based the same for everyone... since many people have creative ways to buy miners that they cant really do the same on buying BTC, then the cost basis drops which means they can mine less BTC and still make ROI
I know this is hard for the old skool stackers to understand and swallow, but just look around.. there must be a reason that pre-orders still sell well even though the BTC in / BTC out never adds up anymore right?
Not really disagreeing with you, just pointing out how things have changed
/reality
Very well put. I, for example, bought BFL hardware. I spent $22,500 on singles (Thanks to AMEX), ended up with 410BTC (and rising) sold 200ish @ $130 avg, so $26,000 return. Factor in interest on my card, I've got my card paid off, and about $1,000 in my bank account. That's a positive ROI.
Of course if I bought BTC with my $22k, I'd be sitting pretty, but the bottom line is I had a positive ROI (With 210+ BTC in unrealized gains). That being said, I paid in $USD, my ROI is based on $USD. Had I paid BFL in BTC, I may very well feel different.
Another way of looking at is, I bought a 1st gen iPhone, sold it on craigslist, made $200. But since I didn't buy AAPL @ $123 that day, I'm facing a negative ROI.
When will people get it through their heads that it does not matter whether you pay for your mines in BTC, dollars, yen, or whatever!!!??? MONEY IS MONEY! Especially money like US dollars and btc which is freely convertible.
The fact is you would have had more money if you had bought btc instead. It doesn't mean you made a poor investment. It was obviously better than letting your money sit as dollars. But it was not as good as investing in bitcoins directly. And miners must always compare their returns with that option. It never makes sense to mine if it will be cheaper to buy bitcoins directly.