Well, I think it would be pretty easy to take the best ideas from HTML/CSS and make something MUCH MUCH better that would be completely incompatible with these- See for instance subform (https://medium.com/subform) The problem with this of course is that these alternative systems aren't widely supported, but at some point I expect one of the AFGAMs to publish and push one of these alternate layout systems and attempt to get higher adoption.

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