i would prefer NOT to see the spvp implemented, period, for all the reasons i've already made ad nauseum. let them experiment on federated servers.
i'm not even sure how you'd bring an altcoin into a SC with spvp since the monetary properties of such altcoins are usually so divergent and non-sensical to most Bitcoiners it wouldn't be worth anyone's time or effort.
If Side Chains run adequately on say LTC for long enough to see some of the tail risks play out, and we figure out how to handle those, then I would see that as a beneficial outcome.
On the other hand, some of the pernicious effects may take a very long time to work out, but we'd see them on LTC well before we'd see them on BTC. (Or even better some new coin designed with this as its purpose.)
That's the problem with tail risks. How do you know what is a "long enough time?"
This is why the catastrophic failure issue suggests there shouldn't really be one coin after all, and trying to maximize "network effect" may be over-fitting. Monoculture is fragile.
There absolutely should be one coin/ledger but is it imperative that there be one protocol/chain to update it?
Maybe multiple chains could allow us to manage the risk of one failed blockchain bringing its coin down with it?
And what if the coin itself fails, perhaps for economic rather than technical reasons? Or if having multiple blockchains (or other such technologies) too tightly interconnected by a single coin allows for contagion type effects? This is not unprecedented.
We don't have a single currency in the world today, and not even a single reserve currency (where presumably the network effect of liquidity could reign supreme, unfettered by legal tender laws, etc.). I doubt in the history of civilization we ever really have, except perhaps in some isolated simple economies. If the dollar fails, then we can turn to sterling, or bitcoin, or renminbi, or gold. The world has a way of recognizing fragile over-optimization and avoiding it, though sometimes this process takes the form of going to far and having a catastrophic failure first.
One single coin to rule them all is a catastrophe waiting to happen. I doubt that happens though. People recognize the risk and avoid it, which is likely why something like LTC has any value at all (though LTC isn't really the best for this and will likely be overtaken). It isn't for features or even marketing.
there are huge advantages and efficiencies to developing a one world currency that is apolitical and controlled by the will of the majority of ppl. we can't imagine it from a digital standpoint except in the context of physical gold which actually worked pretty well for centuries.
but to deny that it is possible is to deny the revolution of open source coding which is a grassroots concept. as Gavin says, if there is a problem, we'll fix it.