Hi IO540,
The term "sensitive altimeter" describes an altimeter whose most precise increment of indiction would be less than 100 feet (usually 20 feet). It would be unlikely that pilots of "modern" certified aircraft would have ever flown with anything else. I did fly an Ercoupe many years ago which had an "altimeter". It's most precise pointer would indicate an altitude change of two thousand feet per one revolution of the pointer - was that ever confusing! I believe now minimum equipment regulations for aircraft, require the installation of a sensitive altimeter, which excludes the use of any other type for primary altitude information.
A sensitive altimeter is even more in need of vibration during calibration, as it has a mechanism somewhat similar to ht of an airspeed indicator, but also a reduction gearbox which drives the thousands and tens of thousands pointers from the primary pointer. It's a lot of mechanical drag to overcome with only atmospheric pressure driving everything.
Cheers, Pilot DAR