Did you see the new Surface Book? It has a GPU in th base of the device, that gives extra power when plugged in. I believe a big reason Microsoft is doing this is a learn how to best add processing power dynamically when docking.
A Surface phone with x86 will have a docking station with extra processing power, I reckon. Your company will have flexible office spaces where people can dock their phones and it WILL be like a desktop machine, even in terms of performance. Imagine all the costs saved for the company, while ease of use is maintained for the employee.
Oh, and for those actually needing a laptop the will be a lapdock like the Motorola Atrix (cf. Motorola Atrix 4G Lapdock review - Engadget ) that can be shared between all employees when they need them. Same concept, with processing power in the base.
Once again that seems like something businesses MIGHT like if sold properly to them, not the average consumer, at least not in a way that's going to change sales much in the next year or two. I don't doubt the Surface Phone (if released as described) would do great things. It would also be very expensive, and it will almost certainly NOT pull Windows Phone out of the rut that it's in now.