So, when is the last time that Glock....

[Schuetzenman]

What does demand for current production have to do with new design?

If the design group is busy with current product; then there are problems which Glock doesn't have...

Often a lot. If you can't make enough of what you already make often a company doesn't look past the present. You assume they have a desgin group, might be two guys in a a cubical. I doubt Glock is like automotive industry, examples GM or Ford. Their idea of design seems to be about adding a rail, changing the grip texture or maybe a introducing a new chambering every 5 to 10 years.