The local Mazda Demo/Advanced Driving day recommended keeping DSC on for the entire circuit and also showed faster progress around the circuit with it kept on. I agree with Mal, the DSC is not some figment of an engineer's imagination but is there for a purpose and if one is going to turn it off as a matter of almost routine, then one needs to be aware of the quincequonces.
I had a memorable DSC intervention that ostensibly saved my car from spearing sideways into a semitrailer at over 130kmh on a long sweeper when I hit a deeper than normal patch of standing water on the road, and which I was forced to drive through by virtue of the truck's positioning on my side of the centreline. It reacted quickly and positively and faster than I could have. While I obviously can't say what the outcome might have been if I had DSC off, I was impressed with the way it dealt with the situation.
CP_e Standback & PNP; CP_e 3" SS Downpipe; Corksport FMIC with Top-mount K&N filter & OEM Ram CAI; Turbosmart BOV; Dashhawk; Prosport Boost Guage; JBR solid shift bushes; DBA 4000 Wiper-Slot front rotors; Hawk Ferro-Carbon HPS Street front brake pads (@ 69,000km); Sumitomo HTRZIII's in 225/45 x 18