If you really want to work on details (like sharpening and noise reduction), then Lightroom Mobile isn't the tool for you, as it does work on lower-res images than the original photo. If you want to work on macro features such as exposure, contrast, saturation, etc., Lightroom mobile is fine and thus is not pointless.
There is no correct workflow .... just what works for you.....
Paige is correct, detail is lacking as smart previews are used... band width is not suitable for full res files at this time.
However I am seeing plenty of good stuff with Lr Mobile, Ps Mix, Fix, etc.... but of course I have only seen them on the net... if that is your use great. If you want 5x3 metre displays, then these are probably not the tools.....
it depends on what final outcome your images are being created for. Print and web are ideal hence the need for highest quality. My pointless comment was more directed for The fact Lightroom mobile shrinks the file sizes before you work on them.
Until an update hits to resolve this then I'll be using the work around of full size images to Dropbox then retouch using fix and mix from there.