All that said (and I'm a natural skeptic) I had enough confidence...or something...in Bitcoin to take a decent sized position, a majority of which I hold today. I anticipated subordinate chains as the most tenable scaling mechanism from a very early time in my involvement, and with 'sidechains' that looks to be within grasp. If they can be available and leveraged before those who wish to 'embrace, extend, and extinguish' Bitcoin then there is still hope for the solution.
Sidechains can not be done in a trustless manner without a hard fork of the Bitcoin protocol. Additional opcodes or other mechanisms need to be introduced to allow validating the SPV proof for the sidechain. There is no evidence that there is sufficient support for a hard fork to support sidechain SPV proofs. If the block size is not raised as blocks become fuller, delays become longer, and fees become higher any support for a hard fork to add SPV proofs will evaporate. SPV proof are significantly larger than the average mainchain txn and the potential of multiple sidechains means it would consume valuable blockspace.
Last I heard, the (optional but safe, desirable, and broadly useful) SPV proof opcode was a
soft fork. Wanna 'splain your interpretation?
Secondly, I don't mind at all if a peg operation takes days. In fact I prefer that. It's much easier to secure. I don't want to belabor the point, but it seems necessary: If every transaction I do does not meet the rigorous standards of security that I demand of Bitcoin, I. DON'T. CARE! In fact I see it as a huge positive. If native Bitcoin is used mostly by people who know what they are doing, that almost single-handedly solves all of the fraud, theft, and accident problems which have vexed the ecosystem over the last number of years I've been around. That is but one reason of many that I make this statement.
Sidechains would derive their strength from the same standards of openness and confidence in dev that Bitcoin does today, but would have their value backstopped by the all confidence that Bitcoin itself can muster. The one key critical aspect of a crypto-currency system tied to a backing store would be the backing store itself. One fuck-up and that is gone. Exponential growth would certainly be such a fuck-up.
So to pin your hopes on sidechains and keeping the 1MB limit is just silly. Honestly I would love to see a hard fork to add SPV proofs and fix some low level plumbing of the main chain at the same time but it may never happen. It certainly isn't going to happen in a scenario where users are finding it increasingly more difficult and expensive to use bitcoin for their transactions.
I've said it before and I'll say it again, I don't mind exceeding the 1 MB limit when it is shown to be desirable as part of an ecosystem which itself has some theoretical hope of being robust and sustainable at scale. A 'one-size-fits-all' Bitcoin as some sort of a one-world currency for every use imaginable is FAR from this theoretical potential. And that's only one of many reasons to reject this absurd pipe-dream.