I doubt it. Why would someone throw a low-strength punch at you unless you had thrown down? If somebody wants to use force on you for some end (kill you, rob you, abduct you, etc), they are not going to waste their time standing in plain virew boxing with you. You are better off learning how to handle unexpected, forceful attacks, and learning how to stay out of fights you can avoid.
It's a valuable thing to learn on the side but too much of it makes you fight, which I think tends to spell trouble.
I've seen a lot of fights that start with "low-strength" punches. Typically starting with pushing-shoving-punching and escalation. People who have gotten into fights before (and there are a lot of them in some neighborhoods) or anyone with a little experience (a lot of mma guys out there these days) are rarely going to start something with a haymaker. Even if they do - is expecting them to start with what is arguably the most easily handled scenario really a good training strategy?
And no, it's often not that easy to disengage, even from a "low-strength" punch, and it's not really a great training strategy to depend upon it.