A few years ago i asked the same question and my instructor ( well known so no names ) said we could practice one or two . First one from 400ft was no real problem but you learn straightaway that forward on the cyclic is NOT the done thing as it turns you into a javelin and you will be vertical nose down . So we then did one from 300 ft , roll off throttle , down collective , immediate cyclic back a bit and flare and then on ground . This time it seemed to be all very quick indeed ...it is then that i point out the altimeter is still at around 70ft !! I think in the right hands you can get a 206 down from any speed/hight .