I like the idea of distinguishing "seamless" from "seamful." Due to technological limitation, delays and uncertainties are inevitable, especially in sensor-rich systems. But one important argument is that the designers should take the positive design approach - "allows seams to become a resource for users, rather than a system failing."
It is not to say that designing a "seamful" system is always better than a "seamless" system. I think the most important thing is to understand the nature and characteristics of the system, and use the best resources to design out the negative aspects that my exists and presented to the users.