A quick update on my "light strike" situation.
My Glock is approx 20 years old and has been my primary competition handgun for all of that time. Given an annual ammo expenditure of approximately 1-3000 rounds per year, that means it ha fired between 20,000 to 60,000 rounds of 9mm. The striker spring, firing pin spacer sleeve and channel liner were still the original ones. On examination the sleeve and liner appeared to have worn. The striker spring also appeared to have lost a bit tension. I've now replaced them with new OEM Glock parts. When examined side by side, there was a considerable difference in tension between the old spring and the new spring.
I've now put a bit over 200 rounds through the Glock (still with the Timney trigger) since updating the parts. None resulted in light strikes. I suspect that the trigger functions perfectly and that the light strikes were the result of old and tired parts. I believe it was just a coincidence of timing that the failures occurred at the same time as the new trigger was fitted.