Throttle response delays in low gears???

I've always meant to put this question out here!
The craic is, When in 1st or 2nd gear you can be driving along at any speed/rpm and quickly jab the throttle (on off real quick) with no affect or reaction from the car! But in 3rd, 4th ,5th and 6th she instantly responds to any throttle input!!!
Also whaen coasting (rolling with clutch engaged and engine ticking over) the delay is there but when stopped with clutch engaged there is instant response!!!!! :dunno:
Has anyone ever come across this before??? And what do you think it's in aid of???
She has drive by wire and was last mapped by powerstation!
Bob Rawle is road mapping her next month! I don't know if this can be "mapped" out of it or not!!
Any comments would be very welcome!
Thanx lads/ladies
Dan

its probably there for a reason to stop the car lurching forward..different in 4th or what ever but it 1st if you had that instant torque response it would obviously throw the car forward more...just a thought

The delay isn't there when i initially pull away! ie. releasing the clutch at stand still to engage 1st gear!
Thanx for your input though! It's a weird one isn't it!
Dan

yes I also experience this in my 02 sti but i think it only happens when running 95ron, when it has octane boost in it is much smoother.