I tested the vibration-off effect the last couple of days and did not get the reported improvements. These inter-user comparisons, however, are problematic because our use patterns and device characteristics and settings are too diverse. I wouldn't deny irfan's own data/experience, but I would doubt that many others could duplicate it -for this intervention or most others.
I can't easily compare my own use patterns from one day to the next. I have two cheap backup batteries that I've wanted to compare with the Samsung, but it's just to hard to control for my own daily variability. I think they are not as good, but I haven't been able to come up with any good estimates that I could report. Anyway, if I were to guesstimate the vibration-off improvement for my Focus profile and my usage these two days, I'd say 10-15 percent. Not worth it to me -then again, I'm used to just popping in another battery as needed and not worrying about battery life.