Sure. I oversimplified with the point being that two cores and two operating systems allow both operating systems to be doing useful things simultaneously without significantly degrading overall system performance compared to uni-processor, uni-core laptops that everyone has today. Hence, not only will we be able to run Windows and Mac OS at the same time, but thanks to a dual-core processor, we could run them at the same time at high speed. In reality, bus, memory, and disk contention will create traffic jams. Disk contention may be the biggest drawback, but it could be mitigated by separate hard drives (not so easy to do in a laptop).