Not having done 1,000 km yet, the shifts are still stiff under throttle. In fact only 2 in the most used 8-14 range seem to be possible without the flick, 9-10 & 13-14. According to the manual, falling in neutral gear is possible while shifting under pressure (throttle).
From the Rohloff manual:
When changing, gear coupling elements inside the hub must move and when there is more pressure on the pedals it is obvious there is more pressure on these coupling elements resulting in a harder gear change. Whilst stationary or when there is less pressure on the pedals, the twist shifter has less resistance and therefore a lighter gear change is possible. In a situation whereby it is not possible to reduce the pressure on the pedals (e.g. hill climbing), it is still possible to change gear quickly and smoothly. Simply change gear when the cranks are in a straight up-down position where hardly any pressure is being applied upon the pedals.
ATTENTION
Changing gear with the Rohloff SPEEDHUB 500/14 with pressure on the pedals is not necessary when being used appropriately. However due to the robust construction of the Rohloff SPEEDHUB 500/14 changing gear under pressure is possible and is not harmful to the hub. It is however possible that when changing gears under high pressure the hub could accidentally fall into a neutral gear, this is due to the coupling elements not seating correctly into the next elements and therefore rebounding back. If this occurs the rider could lose balance and crash. Changing gears under high pressure is at the riders own risk.
Particulars:
If changing up and down slowly or under high pressure between the gears #7 and #8, it is possible to fall momentarily into gear #11 or #14.