Yes, when you have the correct setting for the printer & paper in 'Preferences', this works well in proof and actual print.

A missing link is in place: one can sort ones pics so they look good on both web and prints.

I have got round the print sizing problem by creating some custom paper sizes a few mm larger than A4 etc and with top, left and right margins set at 0.1. This produces prints as near to the edge of the paper as the system ever allows, about 3mm. My Epson 1290 is now quite old and Epson never did a proper driver for OS10 using its 'borderless' printing facility. Anyway that is as good as DPP. Small sample tests can be done using the 2up etc; inelegant but works.

Incidentally you said it was possible to 'stamp' or 'clone'? I can see you can do this using the 'selection brush' for say sensor spots on a plain sky or even painting over sheep ear tags ditto and getting texture back with 'add grain/noise'...but the latter takes quite a lot of time compared to 'stamp', do you have another trick up your sleeve?