Sorry Genghis. Not sure I get your point. Mike was talking of very big dimensional differences was he not? I was suggesting crashes would not occur until dimensional differences were huge
I reckon all aircraft off a prod line are different and adjustments are made accordingly during prod flt test. Certainly at Dunsfold we documented the L&D trim adjustments needed to make the aircraft fly straight in conventional flight very pedantically. The trim gauges were then re-zeroed with the trims in the necessary flight position and the whole thing reflown again. In PJB it was harder to get consistency as we were up against engine related variations in swirl and from nozzle trimming to get required RPM/JPT relationships. But all this meant was that we had to set the tolerances wider. The max we accepted was 0.06 lateral g out of trim at mid transition speeds and if it was more than that then really big measures were taken from changing nozzles to changing engines.
Re stalling behaviour (not performance) I happen to know that each HS125 was fitted with individual breaker strips as required following flight checks in order to to get consistent handling across the fleet.
One could go on but I suspect you get my point