You make good points, as usual. (Should I say, "as always"?)
I don't think the missing var str
in the your example is the best illustration of the possible problem. Certainly Chrome, for example, says
Uncaught ReferenceError: str is not defined
Hard to misunderstand that error.
Hmmm...What does MSIE say?
***WOW!!*** MSIE 9 allows it!!!!
I didn't realize that MSIE 9 didn't pay attention to "use strict"!
No wonder I do all my debugging in Chrome! <grin/>
Well, you certainly have made your point, at least for those who still use MSIE for coding /debugging!!!