I believe the clutch is supported in Shift, just not in the exact same way it is supported in GT5
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. Correct me if I'm wrong, guys, but I believe the car will shift into the next gear without the use of the clutch, but it will not change as quickly as when the clutch is used. I know (Shift) downshifts are challenging if you just bang through gears without the clutch. I can't comment on the speed of shifting, it's been a while since I've played prologue.
To be honest, I've shifted my street cars without a clutch multiple times (drag racing, hooning, etc..). The only time I've done it and gotten a 'box of neutrals,' as you call it, was when I broke the shaft 3rd and 4th gear ride on in my Jeep. Otherwise, a shift without the clutch just bangs into the gear requested by the driver, similar to Shift.
Granted, it doesn't sound pretty, and isn't the perfect idea of 'babying a car,' but it definately doesn't automatically shift the car into neutral and make you re-engage the clutch to try the gear again, I can tell ya that.
Does the clutch act differently than GT5P? Surely it does. Does it mean that a clutch pedal is not supported at all in Shift? Not in the least bit.