Should be, but as mentioned, there have been a few times where it didn't work. Our latest hardtail 29r rear brake is one. Other times I've had to shim to align rigid mounted calipers, and even had a few that required using the special spotface tool sold by Magura to true the frames mount points. Now most frame builders do this prior to shipping. Pretty bad when you need to machine a brand new high end frame with the manufacturers blessings.

It likely is the fork, the brake caliper needs to be removed to return the fork, so why not see if it aligns parallel during diasassembly?

Just a thought, and easy to do and verify.

PK