it was a bit of both - "why on Earth did that happen?" and being told that smaller was better since the jpeg is being included as the cover for a script to download on Amazon, and apparently they keep more money based on file size (though I'm not sure what real difference 5 extra MB would make).
From layman's perspective, it struck me as odd that simply adding my name would make such a difference given that the original image is far more complex.
I'd like to keep the original image untouched / unaltered, find a way to add my name while keeping the file around the same size as the original jpeg.
So, if I understand correctly, because the script just going to be used digitally, RGB is better. Is there a button I need to tick or some such when exporting to jpeg that does this or is my only option altering CMYK and using the quality slider / preset dropdown in the export section?
by the way, thank you so much for answering me. Without knowing what sorts of key words and phrases to look up so that I could train myself, getting this far would have taken much more time.
JMF
(quick update while I keep searching online, apparently an extra 5MB in size is a rather substantial cut of what Amazon gives you, so I definitely need to keep the file as small as possible without altering the quality of the original jpeg)