Last weekend I attended to a track day event and during my half an hour session I noticed a big puff of smoke when changing from 3rd to 4th after incidentaly hitting the rev limiter as far I could see it happened only once...
By the light blue colour I could see its was oil being burnt but where did it come from? Apart from that the car ran faultlessly generating on the way back (200mile trip) 0,9bar peak with k16's and an Europipe.

 

I've not heard of this happening to a TT, but it's pretty common in the NA 996s. Have you recently had an oil change? In my car, it happens when the oil level is relatively high (not over-filled, but high). Right when I change gear under hard acceleration.

 

It was right when I changed gear... oil level was 2 bar down from top. I wonder what does it make this puff of smoke... is it oil passing valve guides? Is it the turbos? I just hope its not the turbo(s) going... I even do the 2min cool down everytime I drive the car.

 

If you bounced at the rev limit it would more likely be overfuelling and nothing to be concerned about.