This I think is the biggest shortcoming of Lightroom, no soft proofing. Normaly, professional printer will supply you with a printer profile (I use White House Custom Color and you actually have to proof 5 shots with them using their profile before you can open an account). So in Photoshop you can load that profile into the View -> Proof Setup, and that way you can see what it will look like when printed, and usually those pro printers are serious, so that profile is dead balls on when viewing on a calibrated monitor, it is very satisfying, what you see is what you get. And because you are looking at what it will look like from the printer, you can make any adjustments you need to make that version look good. If Lightroom had soft proofing, it would be even better because you wouldn't need a print copy and an original copy, you could make you changes in the development module and just save it as a virtual copy. So this is one of the very very few cases where I say "Boo Lightroom" - and if Lightroom did have soft proofing, it would solve the issue that we are seeing because you could soft proof in sRGB so you could make any adjustments you need. I have seen a lot of requests to get this in Lightroom (and as soon as I'm done with this, I'm heading over to Adobe to ask for it again)
Once you make those adjustments, most printers want the file tagged sRGB, but more and more are down with the Adobe RGB.
White House sure is proud of their prints, eh? CHA-CHING!
