There is no point in arguing about what is better, freehand or jig. No one will ask how you made knife. I've tried both ways. It's easier with a jig for me , grinding is faster ,belts last longer, I get a much better finish , fewer mistakes. . . . . Also jig works as a heat sink so I can grind longer and I have never overheated blade I'm working on...well...it happens once in a while but very, very rarely...
That's enough reason for me to use it.
If someone wants and can, they can grind steel with their thoughts.