Patrons should use databases and indexes to find articles from credible sources. Information professionals need to teach them how to use Boolean operators, controlled vocabulary, truncation to find relevant articles.
Jargon is language that is only used by a small group.
When you are presenting to people outside of your small group, you need to use language that will be understood by most, if not all of the attendees.
Most people will not continue to read a poster they don't understand, so if you use jargon, most people won't try continuing to read it.
Library users should use library resouces to find quality information. Librarians should teach patrons how to use advanced search techniques.
One of the problems with jargon is that sometimes you don't realize you're using it. If you spend most of your days working with bioinformaticians, you may forget that not everyone uses words like proteomics and glycosylation.
So when you are to do a poster or a presentation to those outsidde of your specialty, find someone outside of our specialty, and ask them to go over your poster or presentation.