Totally agree - in any case the optional comma might have been better served earlier in the sentence. I don't think it makes sense where suggested.
The problem as I see it is that when you have a sentence that needs such clarification via grammar, it would have been better to rewrite and re-express the whole thing, since, by creating long sentences that go on and on and on, with clause upon clause, you create monster constructs of comprehension whose sense has long been forgotten, reading like a limping effort by a panelist from that improvisation radio show "Just a minute", which you feel has started out in hope, gathered pace down some random crevice of involuntary exposition and emerged out the other end whence we are ignorant now of it's original clothing (ripped to shreds as if dragged backwards through a hedge with particularly spiny brambles), yet nevertheless, and not withstanding the specifics of what just happened, the point might have been conveyed to the attentive audience in brief, succinct, parsimonious, individual sentences without redress to elaboration, obfuscation or listing words of ever increasing length from a thesaurus. If you get my drift.
