Maybe the lesson at hand is that there is such a thing as spreading one’s self too thin.  As the dichotomy grows between mass-market celebrity fashion lines and their (astronomically) higher-priced celeb counterparts, one fact seems clear — for a celeb to make that jump upward, it’s exponentially helpful to re-brand one’s self as a designer first and foremost.

While Jessica Simpson is set to earn $1 billion from her wide-ranging, eponymous apparel company, she’s also, well, a pop star.  She still tours.  Her reality days aren’t that far behind her.  She’s made (and by all accounts will continue to make) a more-than-healthy income from her clothing company, but it’s nearly impossible to imagine her launching a line at, say, Bergdorf Goodman.  Meanwhile, when was the last time the words “Spice Girl” were the first to spring to mind regarding Victoria Beckham?  (That’s a look from her Fall 2011 collection pictured at left).  As she debuts a five-figure handbag and shows at Fashion Week to reasonable industry acclaim, the ultimate soccer wife has abandoned her other careers, to the success of her pursuits as a designer.

In another example, the Olsen twins’ the Row, which has been pricey since its launch, recently sold out of its much-ballyhooed $34,000 backpack.  Other than what that says about the current spending habits of the super rich, it also supports at least Ashley Olsen’s singular devotion to her career as a designer (sister Mary-Kate has very lightly continued to pursue acting).   Though they offer lower-priced lines, the twins’ upscale success can partly be attributed to their career commitment to the fashion industry overall.

It seems to be the celebs turning themselves into one-trick design ponies who make measurable headway into the fashion industry’s upper echelons.  Is it the beginning of the end of for slashie careers (reality star/handbag designer, designer/actress, etc.)?  Or, perhaps, the success of certain upscale celebrity clothing lines will simply help demarcate between fame-chasers who’ve emerged as bona fide designers and those who are simply licensing their names for more product.