Wrong, 'I got done', 59 in a 50 (My last ticket, got off it though
) by a laser gun.
Should be ok at 72, usually 10% + 2mph about 79-80 is generally the rule, although it depends what they've been ordered to take you at, could be 80 could be 73-4, only your 14 days will tell, but you should be ok.
Tom