Reuse XMLHttpRequest object or create a new one?
===

I searched stackoverflow but got contradictory answers:

http://stackoverflow.com/questions/2680756/why-should-i-reuse-xmlhttprequest-objects

http://stackoverflow.com/questions/11079543/ajax-intensive-page-reuse-the-same-xmlhttprequest-object-or-create-new-one-ever

Also, there's a recommendation on w3schools.com :

> If you have more than one AJAX task on your website, you should create
> ONE standard function for creating the XMLHttpRequest object, and call
> this for each AJAX task.

Why this recommendation? I'm instead using a global XMLHttpRequest object on my page for handling all Ajax tasks.