Let me try to re-state my opinion.
The question was if steering ability was necessary
, not if it was something nice to have or if it helped tracking.
So I answered the question as asked, and the answer is 'No, it is not necessary.'
Steering/pivot is something that most of you gentlemen wanted or desired, but it's not necessary for the dolly to function. My dolly does not have it and my dolly functions just fine for me.
There seems to be a difference of opinion as to the meaning of the words 'want' and 'need'. You gentlemen 'wanted' steering/pivot ability and purchased accordingly, but you didn't 'need' it, or my dolly would be required to have it too.
So it comes down to this, I'm sure all of you did about the same thing that I did when it came time to buy a dolly, we looked at the various models and compared quality, function, abilities, and price. Then we chose the one that was best suited for our individual needs and bought it.
I think my dolly is better for me and yours is better for you, and I doubt that we are going to convince each other to change our views.