Yes. I had to have my cut and shimmed back properly.

and remember, what you cut off is going to be an opening between the door and threshold, so use a steady hand. don't forget to sand well when you're finished.

I wouldn't go any more than a 1/4"

"....so use a steady hand..."

That's why you use a rail saw. Shake all you please, the cut will be perfect.

The amount of gap needed under a door has to do with the number of HVAC returns spread throughout the home. If you have the modern abomination of a single large air return, you need a much bigger gap that you do if you have proper air returns in each room.

Use an electric planer. If you use a hand saw it might splinter the bottom of the doors.

Thank you for the comments! We have several air returns, but not one in each room. We don't have expensive tools, but I wonder if some of these tools can be rented.

Probably can rent it. You pretty much can rent anything.

Sophie is correct, but who wants to look at an inch and a half gap?