Teaching sales staff C/C++ is way to deep. Teach them coding concepts but not an actual language.
I should have been clearer in the original posting: I also want the sales staff to be able to use the tool they're sellling. It's a high-performance reversible debugging engine that uses gdb as the frontend (over the gdb remote serial protocol, so no GPL issues). So they're going to have to use gdb (I'm thinking via Eclipse or some other graphical frontend).
I guess we could teach them Pascal or some other higher-level compiled language that is supported by gdb. But there are more and better resources out there for C (e.g. I'm not aware of a graphical frontend for gdb with Pascal). Given all that, and given that we're not trying to turn them into useful programmers but just give them a taste of the problems the tool addresses, I sitll think C is the right choice.
a good programmer can program in any language
No, a good programmer can learn any language: in practice we all specialise in some languages (personally I've found I could always do what I need pretty effectively in either C or Python, but I don't get to do much coding these days). But all that is beside the point: regardless of how many languages you know, you need to pick the right one for the job. I acknowledge that it's highly unusual for C to be the right language for an introduction to programming, in this case I think it is.
Put it this way: a sales person doesn't need to understand what it is they're trying to sell, but it sure as hell helps if they do. Note that I'm talking about how it works, but what it does. i.e. this only matters as we sell a fairly "hard-core" development tool (it's effectively a fancy debugger for compiled languages on Linux). If we were selling almost any other kind of software then I wouldn't dream of teaching the sales team to code. (Actually, that's not quite true: I think everyone should be taught at least some programming (e.g at school), but that's really a whole other topic!)
"Take that, you hostile sons-of-bitches!" -- James Coburn, in the finale of _The_President's_Analyst_