Would this work good enough, With out a Notcher ?.
Yes. I think it would. I was building frames that certified welders with lots of experience were doing all the final welds and I was trying to hand them items that met their expectations. I had seen this video and it did help, but at that time the welder asked me if I could get rid of the gaps. I got the notcher and all the gaps went away and it was a one shot deal. I found that with the notcher I did not have gaps and with little or no practice I could get the angle on tubes with the first try. There was no fitting or additional cutting.
The top of this piece on the right is welded to a 4" diameter tube on an angle.
This is the top. The tube is splayed at an angle and the cut is in different planes. This was the first attempt and it was why I liked the notcher. I was not getting this quality doing it by hand.
When I got the notcher I did do a bunch of sample notches on scrap tubing just to get the technique down. It also gave me some pieces that I could keep that were marked with the set-up so I could use them to guess what settings would work. It saved me a huge amount of time. I have not had the need to do many right angle or diagonal cuts that are used on roll cages, which might be easier.
David