I occasionally see newbies typing an explicit superscript number to add a reference instead of using an actual reference. VE could show them some kind of a bubble that teaches how to use a real reference. (This probably shouldn't be a fully automatic replacement, because explicit superscript numbers are sometimes needed.)
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Here's a big example of a good-faith edit from today. It's in Hebrew, but you should be able to see this phenomenon happening fairly easily – search for <sup>.
(The user also tried to create links using explicit [[]], which is a different issue. For some reason I thought that VE is already smart enough to process that in a DWIM way.)