The six month requirement for a 1st class I.R. was onerous and costly for individuals or small operators (but it does mean that I have several more renewals than total years of flying). The 2nd class I.R. and ATPL were inventions aimed at making it difficult for pilots to head off to greener pastures overseas, because the check ride standard was set lower and everyone knew it. Thus QANTAS and TAA effectively dictated pilot licencing terms.
In Australia's diligent pursuit of non-ICAO standards, there was a time when the highest licence a non-airline pilot could hold was a Senior Commercial, though with a First Class I.R. Despite the fact that SCPLs were often flying single-pilot IFR under far more arduous conditions than their airline brethren, sometimes it was hard to get other licencing authorities to accept that this was as good as a First Class ATPL.
If a pilot wanted to fly IFR in the real outside world, most jurisdictions had an Instrument Rating - period. The idea being that you demonstrated once a year that you could keep it right side up in IMC, fly to some sensibly-close tolerances and not get lost in the process. Co-pilots had to fly to the same tolerances. Then the onus was on the individual to maintain recency.
Last edited by Mach E Avelli; 9th May 2013 at 04:41.