Given the fact that people were shorting BITUSD to their heart content (mostly due to bullish on BTSX) without a corresponding stop loss order, their effective "stops" were near the margin call range. So for a big BTSX holder, wanting to buy cheap, it is much easier to trigger a short squeeze or a "stop hunt" by triggering a big sell on some exchanges (arb working out the rest). Something similar happens even in the forex markets. You target a lower end where the stops are to actually buy on a bounce rather than chase the market towards the top.
That is quite some strategy bitmeat, I guess you were into forex trading before all this? And the market liquidity provides much more opportunity here, than what it did in forex, eh?
That said, I have to disagree with the assertion you made in the op. Forex is a rather liquid market and has been running for years (and many gullible traders being pulled in for the 5% a day return promises). While BTSX has some great achievements like the BITUSD, I think retail or small level businesses picking it up is very far off. It will take some real great marketing campaign to actually achieve it. For now I think we will remain in a bit of a range before the actual breakoff comes around.