To answer most of the replies, John, M and all others, seam peaking can be corrected without the SDN but it does make it much easier. It would be similar to saying you do not need a Kool
Glide to make a good seam but it makes it much easier.
Taking apart seams and correcting them is a fairly simple process and very profitable. Understanding what is called 'stress realignment' as to the cause of seam peaking, correct that and the seam will tend to not hinge and not peak. Harry has shared some fantastic work on how to align a seam pattern properly as well as welding a seam.
I would strongly suggest learning this and then market for seam repair, it is one of my personal favorites because it is the number one complaint in carpet installation.
Here is an example of a radical seam put together, that no one would try to do but I show this in my class to show how much a seam can be off and still be put together pretty well.
Here is a large section cut out of a seam area at a very bad angle (no one would try to put this together but is is used for showing how extreme something can be put together; the section taken out is about 3" or so)
Here is the actual two pieces to put together with the end touching showing how off this seam repair would be
Here is the seam put together with matching the large gap so that it fits
The whole exercise it to show how to put together a seam that is very bad. If one understands this, they can easily put together a good seam. Take for example the seam in most doorways, they are often in terrible shape. Most do not want to touch these but they are actually vary simple to take apart and when put back together they do not have to be perfect to look perfect.
SA