I managed to save my e46 from a death slide today too!
Total unexpected loss of rear traction... and all I could think about was this thread hahaha!
Im running 245/40r18 potenzas, and they are getting to the end of thier useable tread.
I accelerated to about 110 on an on ramp with a recommended speed of 70. Usually my car just begs for more, on hard corners, but not today.
This time last year, I had zero traction issues and the tires were almost new. Now they are down to the last 3-4/32nds and Im amazed at how bad they suck with a little rain on a chilly road.
I know for sure my alignment is perfect, and the I have no worn out rear end parts.
Tires make ALL the difference

Like it was said before, try a swap with ur buddy.