I wonder who may have an incentive to code up an alternative implementation? Maybe somebody who already has millions of dollars tied up in capital equipment - someone whose continued profitability requires making any optimization allowed by the protocol...
I'd be happy to write a new client with emphasis purely on performance and scalability from scratch... if someone wanted to throw large sums of money at me to do so and keep sending me more indefinitely to maintain and update it.
Well, that seems a perfectly reasonable stance.
Just as a question ... do you have an estimate of the % of solved blocks that are attributable to your SW?