Unlike PMBs or plain mining hardware, there is a strategy of reinvestment here, and the idea is more or less to increase or at least preserve the % of hashrate of the network as the difficulty grows.
This is bullshit. You can as well invest into mining hardware and reinvest some part of proceedings into more hardware. Sure, it requires some work, but really not that much, I guess.
ASICMINER is very different because it produces hardware itself at relatively low cost, also it
sells hardware to increase capital.
ASICMINER might be able to keep up with growing hashrate (but it's not guaranteed, it all depends on what others will invest and what others will deliver), but let's just say it's much less likely for BASIC-MINING.
And over the last few months, things have been going very well for BM, thanks to the good management of creativex: acquiring the right hardware, at the right time and for a sensible price, basically.
He's buying for a market price. It is sensible, indeed, but anybody can buy devices that way (with some degree of luck).