This is an interesting topic for me, a fairly experienced rider. I used to always push higher gears and a lower cadence. I have very strong legs, and this was the easiest for me.
When I bought my new bike, I had a cadence meter put on and spent a lot of time on a trainer, trying to match the cadence Coach Sean recommended. The first two to three weeks I did this, I huffed and puffed and thought I'd keel over. But, I ended up with a higher cadence and a lower gear and was actually faster, especially up hill.
I've spent the summer outside (yay!) on my bike, so I haven't been watching cadence, but I am faster. However, i still ride big gears - but at a higher spin - especially on the flats and rolling hills. I'm not built to have a very high cadence spin - 90 is still tough unless it's a low, low gear - I average about 80. I still have very strong legs, so a bit of both seems to work best for me.
So, that's my long winded why of saying try both and find out what works best for you.
Christine
Life is not measured by the number of breaths we take, but by the moments that take our breath away.
Cycle! It's Good for the Wattle; it's good for the can!