Real, modern day Spitfires are started the same way like the original pilot's notes say, the only exception is (with some operators) to switch magnetos ON only after two prop turns (but the engine would start anyway even with the mags ON before the start, of course). I don't quite understand why DCS Spit requires different procedure (simulator limits?). I think that a real Spit would start even if using the DCS's procedure (but I have never tried, just in case), I mean Idle cut-off control forward when the engine starts to pick-up on a priming charge, like on Allisons. But what I don't understand at all is the reverse sequence of booster pump and priming. In all planes I have flown so far you pressurize the fuel system first, then prime. It saves a lot of unnecessary pumping of primer before it sucks some fuel from empty or unpressurized fuel pipes.
Just a technical side note, booster/wobble pump does not pressurize the fuel tank, it pressurizes the fuel line between the fuel tank and carburator and helps to keep the fuel pressure when an engine driven fuel pressure pump is not working (engine is shut down). It is not absolutely neccessary for engine operations, keep in mind that Merlin 61/63 equipped Spitfires F Mk.IXc (and olders Marks) had neither booster or wobble pumps. The tank pressurization is performed the different way (air pressure) and is not required for low-level operations
