If the guy designed software for a living, he's a programmer, not an IT guy. IT guys deal in hardware and system software, network comm.
I'm a programmer and I couldn't tell a Cisco box from a Crisco box.
That's more of a literacy issue than an IT issue..
But I've had to deal with other IT people in similar situations as well.. they may specialize in Configuring servers, but someone else builds them...people working on computers in general are like doctors… There are GP’s (basic repair people), then the specialists..(Programmers, Server Admin’s, etc..)…
I have also had quite a few customer's tell me that so and so is a Programmer, so they can fix my computer.... many of those have come back with the system worse than before.... I can do a lot of computer repairs, but programming is beyond me (unless you count some Basic i used to do and DOS batch files..)