Of course [the exchange rate] matters. It means you could have sold, waited and bought back and gotten more coins than you had. And pretending that dollar prices are irrelevant because they are "bankster fiat" is just incredibly disingenuous.
(emphasis mine)
Hindsight is always twenty-twenty, which can be a
byatch sometimes. If you're actively daytrading (hopefully on an exchange that doesn't lag badly when trade volume surpasses 2000 satoshi per hour
), selling hoping to buy back profitably at a (significantly) lower price is a perfectly reasonable strategy. I'm not having a go at those who know what they're doing and attempt this (I was doing it myself on BTC-e not so many moons ago); the only beef I have is if anyone is naïve enough to believe that such strategies aren't gambling (because you don't
know the price will dip x per cent until after the fact). Same deal applies to buying at a loss on the way up from a trough in which one sold low.
In the bitcoin marketplace, history tends to suggest that a simple buy and hold strategy (cold storage, we love you), while perhaps far from perfectly optimal, is probably still by far the best (and least stressful) route for non-super-expert daytraders. As for the exchange rate determining buying power when paying
BTC to a BitPay site, etc., yes, obviously the $ price is important there, but TBH I was spending my bitcoin when I wanted/needed to, even when the exchange rate was <$15. I actually chuckle about recently buying a whole year's VPN
abonnement for about 320 mBTC, when I paid 530 mBTC for a month's access with the same company in January!
But, if you buy and hold
BTC1, then the price gyrates on Gox, you still always have
BTC1. Another analogy: you buy a gold nugget for $600.
You are now $600 poorer and one gold nugget richer. So if the official (scoff) spot price of that gold nugget changes to $700 or $500 whatever... nothing has changed, see preceding bold statement, which still applies.
Welcome to Bitcoinia, buckle up and enjoy the ride.