Dies Irae! I won't steal Faldage's thunder (yes, there's a pun there ) by explaining his witicism , and while I can't think of another example of such (yet) I must address the grammar point brought up:

There is nothing incorrect in English in saying "I was at a workshop," or inverting it for that matter (and love anastrophes I do!). That a structure is inexistent in one language does not make it incorrect in another. Were we to use that logic, then the Spanish "No tengo nada" would be incorrect simply because double negatives are ungrammatical in English.