>I recognise that as programs evolve they optimise for different types of users. >My preference would be "Not to have" the Enhance thin lines option. > Exactly.  For you, you'd like it not to do that.  For other users, they want it to happen.   That's why it's a preference FWIW: That setting was created to work around a problem in some 3rd party PDF creation applications for office-class applications where the lines of a spreadsheet or table would disappear when viewed in Acrobat becuse they were "too thin".  Given that were more of those out there than 'outlined text'-based PDFs, we set the defaults to match the more common case. As to issues with Illustrator' PDF export - I am not aware of any problems with text export in that application.  If you know of a thread or a specific bug number, I am happy to investigate. ... View more