[Ducati] cheap power gain ?

[Philippe Coulon]

Hello
I changed the bottom exhaust pipe (due to trialing on the walkway in the 
traffic jams).
I noticed on the new and old part that the welding created some 
protuberances in the exhaust pipe (up to 5mm for the biggest).
Dremelling them away with the flexible instrument seems easy (I succeded 
on the old pipe ). I am not talking about polishing, just removing metal 
that shoud not have been there in the first place.
But will it have mesurable effect.
The psychological one is there : no uglly welds inside.
Did someone did that and dyno ?

Philippe