Welcome CJ. It's not ignorance...that's information that only people who are going through the transplant process would really know. Every case is different, so I can only tell you mine.
I started my evaluations when my FEV1 was 40%. I had to start a little early because I had to have a liver too and the doctors knew that it would be a longer process for me. I was also having frequent infections and coughing up blood about once every two months...not just a couple of teaspoons, most times, nearly a cup of blood. There are a lot of factors that go into who needs a transplant and when. My FEV1 was falling rather quickly, I was on IV's more often than not, my O2 levels were falling, I couldn't keep weight on, and I was coughing up blood. Even with all of that, I was still told at my transplant center that I was likely too well for transplant, but they wanted to continue to see me and list me when I was ready.
After I had gone to Cleveland for two evaluations (first time for lungs, second time for liver) I found out that I was pregnant and I wouldn't terminate the pregnancy, so I had to hold off on the transplant process until after my son was born. I went back to Cleveland 2 months after he was born, finished some more evaluations, had some more tests done, and was finally listed for lungs and liver in August 2006.
By the time I was transplanted in January 2007, my FEV1 was only about 10%. I had a large bleed of about 4 cups of blood 8 days before I had the transplant. I had been told that if I had another bleed like that, I wouldn't make it to transplant because I would likely be too sick.
Anyway, what I always tell people is it's better to start early (or as early as they will let you) with the evaluations because then you are established with a transplant center, and they can list you when you are ready. It's better to be tested ealry and get everything done, than to test too late and not make it to transplant.