In the early ‘90s he did a series of track tests for Autosport. One was definitely of a Maserati 250F, and I’m pretty sure that some of the others were also older cars with manual gear changing.
Actually, thinking about it, one of DC's biggest strengths was making lightning fast starts, back in the junior formulae and early F1, when clutches and gear shifting were still the norm. I recall in F3, he fought out the season against Barrichello, who invariably took pole whilst DC muffed qualifying (which was NOT one of his biggest strengths). But come the start, DC would rocket off the line and be right with Rubens at turn 1. Unfortunately, in came semi autos and so on and DC's trump card was no longer an advantage. So he really did know his clutch from his gear lever.