localhost and website add problem

Unless you intend to do some serious "offline" work, and wish to TEST your modifications, there is no real need to install on a LOCAL machine.
To go off-topic somewhat, I would argue a local test server should be seen as absolutely essential to test ALL modifications thoroughly, however minor, before uploading to the live one. Additionally its far easier to search for code locally, do modification merges etc.

We have a dedicated DEV zone on a web server, remotely hosted, set up under all indentical conditions to our live hosting.

Trouble with LOCAL (XAMPP) is that it does not precisely mirror a live webserver.

Trouble with LOCAL (XAMPP) is that it does not precisely mirror a live webserver.
Agreed. When I get an odd problem I use a real test webserver. Still, I think the useability of a local install as regards to finding stuff is a big advantage for both new users and semi-experienced users.

*Moderator comment: Let's try to stay on-topic. If you want to debate or praise the merits of a localhost setup, take it to a more appropriate place, instead of hijacking someone's request for help with a technical problem.
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