>> the networks where e-mail is blocked are not likely to allow SSH tunnels, VPNs, or Tor connections out either.
> What makes a network that only allows outbound HTTP different than a network that only allows some obscure protocol outbound, or a network that allows no outbound access at all? Should reportbug support DNS-based transmission to get through networks that block HTTP?
no, you should not implement DNS-based transmission, ping based transmission, or other weird new protocols.
But for a bug reporting tool, you should support the common data communication protocols.
> Disallowing inbound access makes sense for security. Disallowing outbound access (with the *possible* exception of port 25 on networks with a pile of infected spam-sending systems that can't just be kicked off the network) makes a network broken.
Here I (and most security people) just disagree with you. It all depends on the purpose of the network, if the network is not intended to talk to the Internet, creating the ability for it to talk directly to the Internet is a bad idea.