Speaking as a fellow sentimental ol' bugger, Peter Benn's commentary 'delay' (a truly nice guy by the way) is a simple case of between Mach 0.98 and Mach 1.02 the displays only showed Mach 1.0. So that's where we get our delay from.
Mach 2 was a bigger 'lie'. Anytime you were above Mach 1.98 the displays would only show Mach 2. (I've been to Mach 2.1 on test fliights but the pesky things still only showed us Mach 2).
Best regards
Dude
