[puffyvolvo]

> knowing something about MTUs

isn't that why MTU discovery exists?

> Write your software to take advantage of the platform it's on, and the stack beneath it

sure, but usually those bits are usually abstracted away still. otherwise cross-compatability or migrating to a different stack becomes a massive pain.

> The simple fact of using http2 might change your organisation from one fat file served from a CDN, into many that load in parallel and quicker.

others have pointed out things like h2push specifically, that was kind of what i meant with the "(much)" in my original comment. Even then with something like nginx supporting server-push on its end, whatever its fronting could effectively be http/2 unaware and still reap some of the benefits. I imagine it wont be long before there are smarter methods to transparently support this stuff.