Digital BW, The Print

Now that QTR will handle jpgs, I thought I'd convert the GG-to-QTR.tif file to jpg so that I can use the 3MK/R1800 workflow with Photoshop Elements. (Because Elements doesn't have Profile Conversion.) But when I went to the layers palette to see the actual correction curve, it was not visible, only the text overlay. So, with my jpg image still on the workspace I instead called up the original tiff version. Now I had the two layers I was accustomed to, with both the text and the curve easily visible, and I was able to drag the curve over and drop it on the image. I could see a shift in the tonal values take place, as expected. Then I saved the new file, again as a jpg. 

Could it be I did something wrong in converting the tiff correction to a jpg? Or shall I just continue using the tiff version when working with a jpg image? Seems to work... but is it ok to lay a tiff curve over a jpg image?  (I also noted that the file size did not increase nearly as much as when I placed the tiff curve correction over a tiff image.)

Thanks!

Paul