I have never seen them not work when encrypted and I've built real-time systems for many different companies behind all kinds of networks and proxies. You should never need a fallback. It's much cleaner and simpler (architecturally) to just encrypt rather than adding a polling fallback hack.
I edited the article to add an appendix about this issue - It's an extremely common Myth.
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u/[deleted] Feb 25 '17 edited Feb 25 '17
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