Hi Brian,

I guess a lot of it comes down to how you've learned to do your "workflow"?

Very early on I'd gotten into the habit of hiding my original curves straight after the Surface had been formed.
I tend not to delete them just in case I need to rebuild or use them to modify the model a bit later on.

This of course means that when any Fillets need doing, the only thing I'm able to select is the Surface.

Hope this helps, Colin