It does help if they know the tools. The main struggle we had wasn't that they weren't smart, most of them were fantastic domain experts who just didn't have that inquisitive tech spark that sets different breeds of IT people apart. There is nothing wrong with being a domain expert who isn't that keen on cutting edge tools, but back then giving them smalltalk was a mistake. VB and powerbuilder were theoretically inferior, but far more productive for guys like that.