You've seemingly ignored the main thrust of my point in order to quibble over what I meant by optimising redraw. Seems dishonest at best.

Do you agree or disagree that a domain-specific layout language with would be faster to render and animate than a general purpose programming language interacting with the DOM? This seems like an undeniable yes.

Do you agree or disagree that such a layout language could supplant some of the uses of JavaScript over the years? This too seems to be an undeniable yes.

So it seems undeniable that modern browsers would be faster than they currently are on the metrics you criticised them as compared to native apps, which seems to be your primary concern.

And you can claim gzip is good enough to eliminate any space savings a more expressive language would yield, but the fact is people still minify their JS and CSS for significant savings, which means even small differences matter; further, domain specific optimisations have significant effects, and a precompiler could perform advanced common subexpression elimination passes to further compress beyond what gzip could dream of without affecting the semantics your layout.

So theoretically and empirically it seems my point that trading off rendering speed for network speed is not only well motivated, but already settled in my favour.

> Do you agree or disagree that a domain-specific layout language with would be faster to render and animate than a general purpose programming language interacting with the DOM? This seems like an undeniable yes.

No. I don't believe this is true. With CSS as a declarative language, we can do global optimizations that are much harder to do than with a general programming language (especially one that's as hostile to static analysis as Scheme!)

> Do you agree or disagree that such a layout language could supplant some of the uses of JavaScript over the years? This too seems to be an undeniable yes.

Sure, but that's not worth slowing down so many Web sites for.

> And you can claim gzip is good enough to eliminate any space savings a more expressive language would yield, but the fact is people still minify their JS and CSS for significant savings, which means even small differences matter

Sure, but it's not worth trading off the rendering performance.

> a precompiler could perform advanced common subexpression elimination passes

Not with Scheme, it sure can't! You can do those dynamically, but not statically.

DSSSL is not Scheme, it's a domain-specific language, which solves nearly all of your objections that aren't conjecture. Domain-specific languages are obviously much more amenable to optimization. Such a stylesheet language can be trivially cache JIT compiled stylesheets, and because they're more expressive, you'd see more reuse across pages, and possibly even across sites. The bandwidth savings are non-linear.