YouTube also put the byte range in the URL rather than using a range request header.
Perhaps it mitigates against proxies stripping the headers, or it simplifies caching.
Perhaps it mitigates against proxies stripping the headers, or it simplifies caching.
One of many reasons to use HTTPS: prevent tampering with your requests and responses.
I find it particularly telling that switching to HTTPS caused many streaming errors to mysteriously vanish, and I suspect ISP / proxy tampering to be part of the cause. I'd love to know more about what their engineers saw though.