I always open my image into photoshop as a smart object (nothing unique to me, I think many use this workflow), which embeds the raw file into the photoshop document and allows me to re-edit any LR changes with ACR. I can add smart filters to that which are then editable was well (such as smart sharpen for creative sharpening). I’ve been working with Focus Magic some and like what I see, which necessitates a copy of the layer. But I can always get back to where I was with the smart object.
Also any time I “clone” heal, I can then no longer edit the original or the healing layer is obvious, but that’s pretty rare. But keeping that layer insures the raw file and it’s edits are always available.
Not to get into the whole “non destructive” terminology again, but bottom line I can always go backwards or start at a previous step, without having to start over from the lightroom generated file.
Printing for me is always from Lightroom, and the only problem I run into is many of my files end up over 4gigs in size requiring a .psb format which Lightroom doesn’t support These means I have to save a flattened version of the file for printing purposes, which is always named xxxxxx-fromPSB.tif so if I need to edit it I know I need to open the PSB from the finder.