I remember doing that too, after some heavy draw toasterised a few of the ATX connector wires. I was quite surprised at the efficiency of the inner ground plan

I remember doing that too, after some heavy draw toasterised a few of the ATX connector wires. I was quite surprised at the efficiency of the inner ground plane(s) in sucking the heat right out of the attempted joint, and ended up requiring 2 irons and a hot-air preheat to actually get it to reflow. Wasn't my machine, but worked fine for years afterwards, I believe.