I agree that PDF files are a nuisance to deal with in document repositories. I implemented a SharePoint clone 10 years ago for a customer in India (yes, a company in India hired a programmer in Arizona). They had 80 MBAs who churned out reports, new revisions, etc. The worst was dealing with analysts who embedded lots of image files in PDFs - they were not searchable and the text could not be extracted for summaries, etc.