Is that something you do on an ultraportable laptop, though? I don't think anyone is arguing that any tablet can replace a proper workstation.

MS' laptop/tablet hybrids are in the 10-12" size range, and is made as an alternative to other laptops and tablets around that size, not as an alternative to an i7 quad core workstation with a high end GPGPU, 32GB RAM and 3 monitors.