Lots of good answers already, but there's one point I didn't see anyone else making already:

strict is a lexical pragma.

The practical significance of this is that you don't have to slap use strict at the top of your old code and swallow the whole elephant in one gulp. As you're revisiting your code to maintain or debug it, you can add strict one sub, or even just one block, at a time, gradually increasing the proportion of the code which is running under strict - and also limiting how much of it is broken at a time as you are in the process of improving it.

In reply to Re: Backdating strict by dsheroh
in thread Backdating strict by Bod

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