Two points in that WiKi that I don't agree with, is that the SU's on the RR Shadows (T Types) did use an automatic choke flap, they did not lower the jet to enrichen the mixture.
In this case the choke flap operated like any fixed jet carburetor and when closed (not all the way) the engine was forced to draw more fuel through the main jet because the choke flap prevented atmosphere from entering into the engine thus enrichening the mixture.

The other is the fuel pump accelerator, although the SU carb did not have one, the hydraulic damper did act like one, allowing the piston to raise quickly on hard acceleration to give it that needed shot of fuel.
However the piston did not raise very much and it didn't have too to give the same action.

When you unscrew the damper and you notice the brass bit at the end of the damper _ it's lose and never fixed tightly to the shaft.
It's that "looseness" that allows the piston to rise just that small amount before the dampening effect takes over.
This allows a small shot of fuel to give a quicker start of the line, like an accelerator pump.
If you ever notice that sometimes your car is sluggish off the light and there is a big cloud of black smoke, that's because the oil in the damper tube is gone.
This allows the piston to rise too far and too fast causing an overly rich mixture from a standing start.
At times so much fuel can flow into the engine, the car will hesitate.

 

Huey ~ we all have to learn. If I don't learn something new every day I'm fed up. The only reason I know about the idle butterfly bypass circuit is that I restored an S Type from a bare shell up including new wiring harnesses.

 

That is really interesting - the responses to my thread has provided me with so much helpful information!!!