It worked so well for Yahoo
Emulating Marissa Mayer doesn't seem to be much of a recipe for success -- if it's the company's success that matters. I understand that Marissa personally did quite well, as I'm sure we all knew she would.
The only way this makes sense for the company is if IBM's board and management have decided to pursue a harvesting strategy -- cut costs, reduce investments, maintain high prices for existing customers, and milk the company dry. The most highly-skilled and marketable employees -- probably also the most expensive -- will leave rather than accept the new conditions. But losing your best people is fine as long as you no longer care about long-term customer satisfaction, particularly if your customers are entangled in your products and the cost of leaving you for a competitor (both in actual costs and process) are so high that they have to continue paying license fees for years as they dig themselves out of your products and into replacement products.
Management and shareholders may end up doing very well with this strategy, but it's not so great for customers and employees.