I think you need to expand a little more on why you feel this is a "known flaw".
A static compression table with proxy authentication fields in it, as if the network between your browser and LAN proxy is somehow the bottleneck, is reasonable?
This is a most over-engineered protocol, one where nobody knows how tables were constructed or from what data and nobody can quantify what the benefits its features will really be. For instance how much is saved by using a huffman encoding instead of a simple LZ encoding or simple store/recall or not compressing it? Nobody knows! Google did some magic research in private and decided on the most complicated compression method, so therefore HTTP/2 must use it.
This HTTP/2 process is insane.
It's not all about compression ratios. From the HPACK spec (https://http2.github.io/http2-spec/compression.html#rfc.sect...):
SPDY [SPDY] initially addressed this redundancy by
compressing header fields using the DEFLATE [DEFLATE]
format, which proved very effective at efficiently
representing the redundant header fields. However, that
approach exposed a security risk as demonstrated by
the CRIME attack(see [CRIME]).
This specification defines HPACK, a new compressor for
header fields which eliminates redundant header fields,
limits vulnerability to known security attacks, and which
has a bounded memory requirement for use in constrained
environments. Potential security concerns for HPACK are
described in Section 7.Good luck with that. Google has been incredibly adept at using the leverage of their search engine to make webmasters adhere to best practices. ("mobile friendly" e-mails lately, anyone?) Once HTTP/2 lands as a default in Chrome, Apache, Nginx, and Netty, of course they'll push HTTP/2-friendly sites higher in search results.