Nobody cares if you mash or spin, what matters is how fast you go. If one focuses on going as fast as they can (for the particular time interval involved), their cadence will figure itself out.
You should definately experiment and see what works best for you. Just understand that what works best for you has nothing to do with anybody else.
In general, mashing will make your muscles work harder, while spinning will make your cardiovascular system (lungs/heart) work harder. You should be able to find a balance where both systems are working as hard as they can at a particular cadence for a particular effort.
Interesting (to me) anecdote: I live at altitude, in Denver, about a mile up. I've found that when racing at sea level, my ideal cadence is higher than it is at home. This doesn't happen naturally, but with a little bit of conscious effort, I can eek out a little bit more power per effort by shifting down and spinning faster than I usually would. My explanation is that the higher oxygen content at sea level allows my cardiovascular system to do more work, and shifts that ideal cadence to a slightly higher number. I admit that this might all be in my head, but I'm pretty sure there's some truth to it.
So don't talk about your cadence like there's some magic way that changing it is going to make you faster. Don't tell me that I need to change mine. Especially if I'm faster than you; I don't need your advice, you should be reading mine. Train more, train harder, train as fast as you possibly can, at whatever cadence it takes.
That is all.