Only tried this with the Caffitaly System. I've been pressing down on the pod to compact/tamp the coffee inside, and I get a consistently good and slower extraction and often a noticeably thicker/viscous brew.
Before it was hit and miss, half of them would extract too quick and be a bit watery. Pressing on the pod, I don't have this problem anymore.
I'm using the Map Bella machine if it matters.