I wasn't talking so much about FXP (File eXchange Protocol) which is site to site transfer, although I do quite a bit of that when I'm working on sites that allow it. If you work on multiple sites and have large files you want to duplicate on another site for whatever reason, FXP is generally a much faster transfer and doesn't require you to download from one and then upload to the other. Saves a step.
What I was saying above, though, is that I often do quite a bit of live editing on a site. Since I have a number of similar sites (or client sites), I sometimes like to duplicate a modification I've made on some of the other sites. The easiest and fastest way to do that is to open another site (in addition to the site I'm working on), open the file on the other site, and simply copy code from the file I just modified to the corresponding file on the second site using copy/paste. Tab between sites, tab between files.
CuteFTP does that better than anything else out there right now, but I'd like to use DFTP instead. I use FXP less often so it isn't as important. Hope that helps explain, or at least doesn't confuse...
