Comment by philipwhiuk
4 hours ago
Old version:
* DNS lookup for MX record
New version
* DNS lookup for A record
* HTTP request for .wellknown/htmp/known_hosts
Not sure why this is being considered as an improvement?
> each mailbox of a domain on a different provider
Why is this useful/necessary or even 'good'?
Id think its for enduser flexibility and convenience. Its more involved to alter DNS records vs just adding a text line to a webpage and hitting that default endpoint as standard. Same way LetsEncrypt allows the easiest setup with the .wellknown endpoint , where a user may not have DNS access beyond the initial A record setup.
It's not a good idea, I'd call it terrible in fact. We have MX Records, might as well use those. If not, use SRV records. Requiring mail server to involved in root of the domain is terrible idea.