[CyberRabbi]

> Should one be interested in having a discussion like this again, I would suggest strictly establishing what "responsive" means (which is a subjective experience)

This has been established for years. This is the basis of building real time systems. For example, Flight control systems absolutely must be responsive, no exceptions. What does that mean? That the system is guaranteed to respond to an input within a maximum time limit. POSIX applications may generally give the appearance of being responsive but absolutely are not unless specially configured. There is no upper bound on how long any operation will complete. This will be apparent the minute your entire system starts to choke because of a misbehaving application. Responsive systems have a hard bound on worst case behavior.