[Tloewald]

No, because I think one of them is kind of wrong (you can be competent and still use jQuery) and three of them are better off replaced by "use jshint".

Also, you'd be surprised how many otherwise competent javascript programmers don't understand this and simply avoid it most of the time. Heck, I wrote some pretty ridiculously awesome (and robust) stuff without really understanding this, and it's quite possible someone telling everyone they need to understand this, doesn't.

[RBerenguel]

99% of the time I can, I avoid this. Only use it when it's the cleanest way to do something... Avoids a few headaches. Of course, this is also helpful, and when it is, it's great.

[spion]

It is possible, but in some cases it may result with inefficient code as JS engines use constructor functions for optimization heuristics.