When I made my fist Bitcoin purchase I didn't want to spend my hard earned Bitcoin's so I bought some and used those. This was the type of action that grows the economy; however I only used Bitcoin because I am an enthusiast.
If the Bitcoin economy were bigger I may be compelled to just buy in. However buying Bitcoin to partake in Bitcoin economy will create a demand for Bitcoin. When you look at the
"innovation adoption curve" that demand will be filled by the innovators who have lots of BTC to sell. The people who build the economy are the Early Adopters paying the price and the benefactors are the Innovators. (the Early Adopters are key to the successful adoption of Bitcoin for mass market appeal )
In my view you need the Early Adopters to adopt Bitcoin and build the economy in order for it to propagate. For that to happen the Early Adopters need a motivation to build the Bitcoin economy. I see wild swings in boom and bust cycles as the ideal stimulant. Boom bust to me is like gambling only you can cashing out without loss if you have a stable supply of BTC, it also creates risk for the hoarders, once one is in the economy one eventually establishes a legitimate way to obtain BTC and cash out during the swing, thus the economy slowly builds, and the Early Adopters benefit. ( That is, what I am doing now except I am trickle mining, as opposed to building the economy. So technically Miners fall in the Innovation stage, and Silk Road would fall in the Early Adopter stage)
Without a transferring of Innovators benefits to the Early adopters benefit, the Fiat to BTC rate will crash. When it crashes the early adopters benefit, and as the Bitcoin economy grows again the innovators benefit disproportionately to the work done by the early adopters and the system crashes again, and this will go on and on until the wealth of the innovators is eroded.
Just like the sun will rise and fall every day and we will have seasons, the system will optimise over time a decade at the least but it is going to be a rough ride and there will be no guarantees, there is a higher probability of a stalemate along the way, but just to be safe you should mine your [btc20] anyway.
There is no point in knowing if it will succeed before it succeeds, if you knew that, you could cheat the system, if you could cheat the system it would fail.
These debates are fundamentally about risk taking. What will cause Bitcoin to fail is the horders unequivocal faith that the system will prevail, and the Early Adopters (labour that builds the economy) choosing life as usual. IE. a stalemate.
This stalemate could be the end of cripocurancy or its collapse, and with all natural systems collapse there is fertile ground for rebirth.