Though I don't share his confidence that code which evolved without strict can be easily fixed with these tools

Um, I don't think I expressed that confidence. I did say:

With modern editors that perform background syntax checking it's pretty quick to identify where variables need to be declared and fix that.

which as BillKSmith points out may be the thin edge of the wedge, as indeed you also imply. However, identifying issues is a huge head start in resolving them!