The viability of this depends on whether she can sell the idea of Yahoo Reborn. To do that, she's going to have to cull a huge number of bad actors from the existing management, PM, engineering, and design staff -- across the board.
The last big move like this I'm aware of was Steve Jobs' Apple take-over, where he managed to turn Apple into a bigger NeXT, and either shunt all the classic Mac OS people to the sidelines, or force them (as much as possible) to adapt.
It wasn't a perfect transition (see: Carbon vs Cocoa and attempts to retire Carbon internally), but it was a pragmatic one, and it worked.
I'm not holding my breath, but it would be a major coup if she can do the same. Unfortunately for her, and unlike Apple's acquisition of NeXT, Yahoo didn't acquire her previous employer -- this would have greatly facilitated the wholesale replacement of entire dysfunctional teams from a new, better talent pool.
While I agree with the first 3 paragraphs of your opinion, I don't understand why Yahoo HAS to acquire Google to make your argument count? NeXT was not on its way to become the next-big-one. It was mostly Steve Jobs who changed things at Apple with other people's help and contribution.
If Marissa Mayer is as good as the general consensus is and has built connections with all these other smart people, I don't see why it would be a surprise if she turns Yahoo around as a genuine competitor. I don't think that she has to achieve this via some 'coupe'. After all, Yahoo has paid her massive amounts. I am sure they believe in her and respect her decisions rather than be upset with it.
"Especially given the currently depressed state of Yahoo stock, and the potentially enormous upside of the stock options that will undoubtedly be available." -- http://news.ycombinator.com/item?id=4282459
"Strictly on market cap alone, there is a lot more headway in YHOO. It's much easier to image their stock (and thus stock options) tripling in the next few years than GOOG. Microsoft ran into this problem when Google was still small." -- http://news.ycombinator.com/item?id=4283129
The last big move like this I'm aware of was Steve Jobs' Apple take-over, where he managed to turn Apple into a bigger NeXT, and either shunt all the classic Mac OS people to the sidelines, or force them (as much as possible) to adapt.
It wasn't a perfect transition (see: Carbon vs Cocoa and attempts to retire Carbon internally), but it was a pragmatic one, and it worked.
I'm not holding my breath, but it would be a major coup if she can do the same. Unfortunately for her, and unlike Apple's acquisition of NeXT, Yahoo didn't acquire her previous employer -- this would have greatly facilitated the wholesale replacement of entire dysfunctional teams from a new, better talent pool.