Leslie,
Not everyone has the same shared experience.
For myself, it is not unusual to run into words or phrases related to the printing industry that I'm not familiar with due to the printing niche I'm involved in. My father studied horticulture and animal husbandry on the "GI Bill" after he got out of "WWII" and worked in both those fields until the year I was born, when he got into producing labels for the nursery and greenhouse industries. He was not formally trained in printing and the training he did get was by professionals that probably weren't formally trained either.
We rarely print on paper and only a very small portion of what we produce has four straight sides. In years past I designed and drew the steel rule dies electronically and sent them to diemakers. There is alot of printing technology that we didn't get involved with because of the nature of our product, and probably much terminology was missed or misapplied or even created within the confines of our facilities, which admittedly could mean something different or mean nothing at all to an outsider. But it would be misleading to leave you with the impression that we don't embrace technology or that we are trailing behind the industry in every area, and I hope that isn't the case. We are just in a niche market with niche needs and our exposure to what everyone else knows is limited, unfortunately.
So, thanks for sharing your insight on the terms "die trace" and "dieline" as that broadens my experience. However, in the interest of understandable communication with almost anyone, I will probably continue to use the term "dieline", not to be stubborn, but to be readily understood by just about everyone.