I think it is much more likely that an ISTJ would be mis-typed as an INTJ. Having read through the ISTJ profile again, I can say that I recognise a lot of it in myself. For example, work ethic, family values, liking to know the facts, procedures, punctuality, not expressing feelings, organising tasks and implementing through to completion.
The biggest difference between myself and the ISTJ profile is that I have always abhored tradition. I've never blindly followed, or followed because people should be respected. In fact, much to my detriment, I often challenge authority, point out flaws in their arguments and will quite often crack a joke about a superior or just make them look stupid. I'm not religious or affiliated to a particular belief or philosophy.
I like to look at the bigger picture, and would be quite ruthless in trying to achieve an ultimate goal (i.e. do whatever it takes regardless of the rules, ethics or morals). I have little sense of my surroundings, of "great sense of space and function, and artistic appreciation". I like things simple and plain. The art I like tends to express a meaning (such as Banksy's work) rather than being great art in itself.
My mother is an ISTJ and we are very similar in many ways (plus I've also managed to pick up some of her neurotic beliefs). We generally get along well but we also have hum-dingers of arguments. She has an aversion to technology or anything new (which may just be a generation thing). She feels like she must send birthday cards, christmas cards and cards for events that I would never have considered to every person she's ever known, otherwise the world will end.
I enjoy thinking about theories, concepts and far fetched ideas (hence my love of science fiction). I'll quite often write programming applications just to find out how a particular function or design works and never put it to any use, preferring instead to move to the next idea. Of course if I'm required to complete a project I will do, but in my own time I like to experiment.