To a large extent, the Euro shambles was caused by silly loans made by Euro banks as Mark Blyth points out. Where a bank makes silly loans under fractional reserve, a bank run tends to ensue. In contrast, under full reserve, there is not much point in bank creditors running.
To be exact, full reserve necessarily involves forcing depositors to choose between having their money lodged in a near 100% safe fashion, and in contrast, having their money loaned on by their bank, in which case the depositor carries the risk (or much of the risk), rather than taxpayers carrying the risk. That “forced choice” is explicitly advocated by Positive Money and others.
The latter “forced choice” can actually be imposed on banks without necessarily adopting full reserve lock stock and barrel. For example John Cochrane advocated “forced choice” in the Wall Street Journal recently without mentioning full reserve.
Thus it’s the forced choice that would actually have ameliorated the Euro shambles rather than full reserve as such. As to exactly why full reserve (which involves “forced choice”) would have ameliorated the Euro shambles, reasons are set out in an article by me on the Positive Money site.