When my memory is still correct the Ferrari 156/85 wasn't a very successful car. I recall they had an awful lot of problems with the fragile engine, especially in the last part of the season. So I think the word "legedary" is a bit misplaced here (and misspelled?).
Stefan Johanson was definitely a talented driver, but he also had an unhealthy amount of bad luck. When he finally arrived in a car in which he could have shown his potential, he first had to remain in the shadow of the late Michele Alboreto (Italian driver in an Italian car) and later was in a team with the dominant Alain Prost, after which he was soon replaced by the very talented Ayrton Senna. Some guy just have bad luck.
Cheers,
Huub