The debate about overcalling light and just how light is has rabid followers on either side. I used to be very aggressive but has tightened up with the occasional very aggressive overcalls - every hand gets judged on it's own merit. The difference is that I try to exercise judgement, not just overcall on any excuse.
People bashing the over-active style should study one of the most successful partnerships over the last decade (including the #1 ranked player in the world) of Lauria-Versace. They are extreme and [probably] capable of judging the merits of this style.
We played them last December in Milan when this occured (vs my team-mates): Versace overcalled 3D in 2nd position (i.e. unpassed partner) over a weak 2S red against white (teams) on Kxx/x/QJTxxxx/QJ !
Lauria had -/ATxxxx/AKx/T8xx and bid 4NT as a good raise over 4S to his right and then passed 5D. Just a spot-on +600 and an auction to reflect upon. My take is that Lauria is normally the more aggressive one (within the partnership) when overcalling.