There's a number of people who have asked questions about this - at the very least it doesn't seem like it's an intuitive control, and could use improvement.

I suggest right-click-and-drag, or wasd. Both are a little more standard.

Well, I have a Microsoft wheel mouse, 2 buttons and a wheel with 2 additional buttons at the sides.  In order to rotate a ship in the design, I had use the Microsoft Mouse and Keyboard Center program and configure one of the side buttons to be a middle-click.

Then I could press this side button and rotate however I wanted.

OK, my 2c....this is NOT intuitive.

The default for the pressing down the wheel is "flip".   Makes sense!  It's Microsoft!

[addition]

Oh, and looking at it again I find I can reprogram the mouse wheel push to also be a middle button press, which as you suggest, it what it "should" have been.