So, for those of us who have no interest in answers that are purely opioion as to why or why we shouldn't use them, is there a way to have the "save xmp" switch in catalog settings turned on by default. I'm using Lightroom v3.6 for Windows 7 64 bit and am comfortable editing the registry or starting the program with a modified shortcut using the command prompt.
It doesn't stay checked by default when you create a new catalog, only for the catalog that you're working in when you check it.
So, yes. The goal is to have the box checked by default every time a new catalog is created.
There's no way to do that. That's because Lightroom works best with a single catalogue and using metadata to categorise and group images. Just imagine one of the situations that might easily occur - the same picture is referenced in two catalogues, and both are set to auto writing. If you don't really know what you are doing, having that option on by default could easily lose the information you've saved to xmp (though of course it's only part of your LR work). So while you can break up control of your workflow into multiple catalogues, there are safeguards such as this.
The goal is to have the box checked by default every time a new catalog is created.
I'm guess that most of us use only one catalog 99% of the time. The question of multiple catalogs comes up from time to time, but as johnbeardy says, Lightroom appears to work best with a single catalog.
Do you find yourself creating new catalogs frequently? If so, why? I'm not being critical: I'm wondering if I've missed some benefit of multiple catalogs that might be relevant to me.
About the only thing you can do is create an empty catalogue with that flag set that you copy to create your new catalogues as you need them. It would be about the same amount of work as going into preferences for a new catalogue, but could perhaps keep you from forgetting to make the change.
I've been creating a catalog for each project that I'm working on so that when I open Lightroom I can just select the image set that I need. I sometimes have as many as ten projects running concurrently so it's just a matter of convenience to be able to open LR and select the appropriate one. Part of the reason for wanting the sidecar files is that I'm the only one working on the files, but I regularly switch systems between a laptop, desktop, and Mac systems at a local college that use Aperture instead of Lightroom. Having the .xmp files in the same folders as the RAWs is a timesaver for me.