Originally posted by tibbitts Correct. However, if you had not even considered buying a Pentax camera before the SMCT generation precisely because Pentax was behind on providing open-aperture metering, and viewed the new technology as being the way forward for Pentax - basically that in buying those SMCTs you were getting in on the beginning of a new generation - then the introduction of the K-mount after such a short time was undeniably a kick in the teeth. A major reason you had chosen Pentax was being taken away if you upgraded to any newer body, and you wouldn't be able to take advantage of any new lens development.
Nothing is perfect. What they didn't do, however, was make whatever lenses you had into expensive paperweights, which was the Canon approach, and to a certain extent the Nikon way.
IIRC, with Nikon, you had 3 choices with regards to non AI lenses.
1) Stop using them.
2) Pay to have them modified.
3) Buy one of the higher end bodies such as the F3 that had the flip up coupling lever. This allowed one to use the lens, but without access to open aperture metering or aperture preferred automatic.
Nikon just got worse from there, with lenses that would mount, but bodies that were bricks with those lenses.
Even Minolta did better than Canikon. When they went AF, they continued to support the SR/MC/MD mount until they were bought by Konica and lost control of the company.
A kick in the teeth would have been the Canon approach.
What Pentax did when they transitioned from M42 to bayonet was at worst, an inconvenience for a small portion of the user base, not a total abandonment of it.
If you want to use pain metaphors, Pentax was more like a stubbed toe than getting one's teeth kicked down one's throat.