So do I understand that you agree with me that a new risk is not introduced? There is always an inherent risk when trusting your Bitcoins to be somewhere else than on the blockchain.
Now to be completely fair, does Sidechain offer new schemes that could potentially abuse and profit from this risk? Probably. But from my point of view this is the nature of the beast : as the technology evolves so does the potential for more elaborate scams.
no i don't agree. i think NL's example is a good one showing increased risk.
ordinary ppl won't necessarily understand the bolded statement as you presume.
Confusion between "did Bitcoin fail me and lose my coins or did a Sidecoin fail me and lose my coins" is a very legitimate issue. I'm worried about this also.
I think a lot of side chains will be seen as services beyond the main chain. For example today if one wants to anonymize coins they need to go use some sort of mixing service, if they lose their coins in the process the service takes the blame though, not bitcoin. I think sidechains will be the same, people have bitcoins and then decided to use some anonymous sidechain service, if they lose their coins I think it will be clear it was the sidechain / service at fault.
If a sidechain is integrated into Bitcoin-qt or blockchain.info to the extent that you're not even aware of the sidechain being used, then I can see the scenario you're describing as being confusing and damaging to Bitcoin. But I think SC's will be implemented in a manner that it is clear when they are being used.
At least that is my expectation / hope.