How does this work if 2 or more people are working on the same program? I then have to understand what other people's pictures mean, so then not much has change

How does this work if 2 or more people are working on the same program? I then have to understand what other people's pictures mean, so then not much has changed: you still have to learn the meaning of symbols, but those symbols are pictures rather than words. In terms of representing structure with pictures, there is a further weakness in that many problems can't be neatly represented in a diagram because they have more than 3 dimensions to them. I think you basic point still stands though: I'm sure we could be more effective about how we navigate around code and express ourselves to the computer.