The problem (or possible risk) is that this can't be proven. If I'm going to invest in this currency I need to know there is some security (read predictability) with 20% of the total value. Let's say that the original group is composed of two dorky guys out of Seattle, and if some major govt. gets to them (which they will if this is ultimately successful) what could happen with 20% of the total btc economy? There are many other scenarios to think of with one secret entity having 20% of the economy.
Think of it. If btc becomes something large there is a anonymous, hidden, secret group that controls 20% of it. That does not play out well with large organizations trying to gauge risk <-- which will be one of the biggest foundations to grow btc.