Juggling these interactions is exactly what makes good language design so difficult and time consuming. In the talk, I mention JS' ten-day design time several times for exactly this reason. Language design is hard and ten days just isn't enough time to carefully consider how everything will fit together. Try to imagine a programmer, even a brilliant one, noticing the map/parseInt interaction ten days after starting to learn JS, especially in 1995 when these high level languages were far less common. Seems unlikely!
Arguably the issue is not with the behavior but rather a deeper design problem within the language itself. Notice that in Obj-C no one would ever get confused regarding the second parameter of parseInt:withRadix:.
