Updating a "deepObserve" and showing those updates in multiple places should work. If it's not, it's an error, one we would like to fix. But to make it easier, so that we don't have to dive through so much code, it would be great if you can reduce the amount of code and simplify the fiddle.
Removing the copying is interesting, if everything is rendered via Mustache then effectively it is the same as always reading with attr()? => yes