I have an unopened MK cartridge that I bought at the same time as the printer, so it's as old as the starter cartridge. I assume because it has been unopened it would not have dried. Are there other factors to consider ?
In that case I would definitely advise agitating the unopened cart before installing it in the printer, and on a regular basis as well, perhaps monthly, since it is not being "agitated" in the printer. And again, with the cart now installed, you will cause no damage by removing and gently agitating the cart and then reinstalling it. Obviously you would be running a nozzle check following the MK switch, and very likely a cleaning cycle will be initiated at that point. If the nozzle check is showing no problems I would perhaps create an 8x10 with black only and print that, just to make sure the MK is in use and flowing properly. Also, create a black ramp from solid black to white and print it. That should exhibit any banding issues that might occur.
Gary