I am not from Laminar Research; just a flight simmer from downunder.
The simple and quick answer is yes. I have a disc set for XP10 and XP11 and your proposal works.with me. But you have to have disc 1 installed in your drive bay for XP to work. If you fail to do so your installation will revert to a demo version which has a limited time period (10 minutes) but not necessarily connected to the internet.
However, I would suggest you connect to the internet at a predetermined set time eg once a week, to ascertain if there has been an update. This is done by starting the internet, insert disc 1 and then start X-Plane. During the boot-up process you will be prompted with a question asking if you want to check for updates. Answer as you chose (yes) but don't check the box regarding Beta versions. Unless you are well conversant with PCs and other software packages that have Beta updates never tick this box.