I remember N.S. (long time marketer) did this a few years ago to his list and really damaged his credibility, at least he admitted it and apologized to what remained of his list. To a "freebie seeker" list well...maybe, but NEVER to your customer list.
I mean you work so hard to build a list and produce a customer, and in one simple crappy offer you ruin months/years of hard work.
Your customer list should be treated like gold. They trusted you enough to open their wallets. Don't send crap that you didn't even try out.
I'm on quite a few Warrior lists from purchasing WSO's many of which mailed out emails for said product, and which I immediately unsubscribed after reading the feedback in the thread. They blackmail you into subscribing for the upgrades, and bombard you with affiliate links some like this one is highly suspect. The thread is probably still at the top of that forum as it has been for the past 2 days (end rant)