Many of us who have long suspected that Groupon was a gaudy but inherently flimsy mansion built on sand are probably clucking our tongues and acting all I told you so. Don’t get me wrong, this blog is a latecomer to Groupon skepticism; it’s only been about 4 months since I wrote in this space about the all too possible downsides of signing your business up to offer Groupon promotional deals: Thinking about a Groupon promo for your biz? Think hard…

But what a four months it’s been. Four months ago, COO Margo Georgiadis had only been on the job 2 months. Now she’s on her way out the Groupon revolving door and back to former employers, Google.

It gets better/worse/you decide…

Not only is Georgiadis the second COO to leave Groupon in 6 months, but Rob Solomon, who held the gig previously, had only been there since early 2010.

Still, the real kick in the gut for Groupon’s initial investors is this: their once much-awaited IPO is now clouded by the company’s acknowledgment to the SEC that reporting the face value of the company’s coupons sold as revenue — instead of first deducting the merchant’s cut — was a bit of misguided accounting (that might have struck some old-fashioned types as a bit of an over reach right on its face) — the correction of which reduced stated revenue for the first half of the year from $1.5 billion to only $688 million — less than half.

As the old calypso song says: house built on a weak foundation, it will not stand.