Dave: Will you check something for me. I just did an edit following the same process I usually use, but instead of editing as a TIF in Elements I edited as PSD. I'm not very good at this stuff, but from what I can see the TIF edit has lost the exif and the PSD has not. Both were converted to JPG using the same settings and both are 800 x 4xx
here is the first one that was edited as a TIF
here is another one that I just did an experiment with and edited in Elements as PSD instead of TIF
You should be able to see exif for the second one but not the first. Let me know what you see. I don't know if it will help anyone else, but if my findings are correct it will solve the mystery for my particular process.