Consistent Use Of WWW / NON-WWW affecting Website Speed, CDN Resolve Time Amongst Others: WHICH ONE TO CHOOSE?

This question is an continuation on another StackOverflow post where no clear answer is given. (Moderators hungry for flagging, pease read this entire post on Stack overflow first!)

SITUATION You give your technically correct, canonical domain URL to a client who will put it on their website. Days go by and they forget what exactly you instructed them that your canonical/prefered domain was. Ever wondered about the practical & technical implications? And so, they choose themselves either of the below domains to list the url on their blog/news/company site:

SCENARIOS

A <a href="www.website.org">...</a>

B <a href="http://website.org">...</a>

C <a href="http://www.website.org">...</a>

GIVEN I know HOW to setup redirect via Apache to 301 all non-preferred ones to the preferred one, as well as how to set the preference in google webmastertools etc etc.

PRIMARY QUESTIONS

• Technically, is there any speed difference between how fast A, B or C domains will load, given proper setup and assuming the others redirect 301 to the preferred one?

• Any DNS resolving time bonuses on speed when setting either for either of above urls?

SECONDARY QUESTIONS

• Which of the three is likely to be published by geeks, programmers and techies? And开发者_如何学运维 which likely to be published by non-geek non-programmers blog/news/companies?

• Is it more ideally if they choose your preferred domain as URL as well as the anchor text e.g. <a href="X">X</a> instead of <a href="X">Y</a> or doesn't this matter at all?

• Why do all major sites use www. when google clearly says that it doesnt matter which you you chose, as long as you choose and stick to it. Still don't you say its strange that Google amongst almost all top ranking websites, use the www instead of non-www?

• as a programmer, which of these domains A, B or C shall I choose to propagate consistenly in my site as well as tell others is my preference?

DNS wise there is no difference, a look up is a look up.

In terms of speed, in general terms again nothing should make a differnce (if for example you specify the virtual host options in the ServerName. You then dont need to do redirections) You could see some issues with cookies if the pages change domains by incorrect links.