I think you have the wrong end of the stick here :-). Although I describe myself as have got into computers via a backdoor, I never used a computer in the course of my work prior to being employed as an operator about 15 years ago. I then moved to programming them about 10.5 years ago.
Prior to that my only use for computers was playing games, looking after personal databases and the odd bit of programming.
The 'backdoor' was, in fact, a couple of friends who got talking about my ability with computers, and one of those was willing to take me on, and I haven't looked back :-).