Guess I still have a lot to learn about cycling and I guess I misunderstood some of the information that is floating around.

I always thought maintaining cadence of around 80-90s was the best, most efficient for legs, better for knees etc etc
I took it as, you should maintain 'that' cadence throughout, flats, descents, climbs, which is why I stated I have to grind.....purely because my cadence gets down to 50-60 just on that tiny stretch of hill.

Anyway, will try all the different techniques you guys have said.