Model versus Year

[Bullwinkle <yd3@nvc.net>]

Years ago, I thought MG's went more by the model: K, J2, etc. The
year of production was not that important.  Changes made were
noted by chasis not date of production.  If one did talk about a
year, it was the actual year  the car was made not the 'model
year.'

When did this model year hype get going?  Was it something we
Americans tacked on because of our domestic producers or when MG
had to comply with federal standards?  Just curious.

Blake