I believe it is the other way around. I've been studying how my car works recently and the manual. Perhaps your coils were connected back-to-front on the dizzy.
Exhaust side plugs are supposed to run all the time and Intake side plugs are switched.
From my experience, the intake side plugs run when the engine is cold, and as it warms up, they stop firing, or fire less often. It is a mixture of the throttle position sensor, and coolant temp sensor that determine whether the intake plugs fire.
Hopefully this can help someone out in future- I had a prob where the car would run fine in the morning, then as it heated up it ran horribly. This was because one of the exhaust plug leads had broken so was not sparking. Once the car heated up causing the intake side plugs to be disabled, there was no spark occurring in one of the cyls - causing my headache