Actually impulsion doesn't have to be when you are going forward. If you collect you still need impulsion.. And going faster doesn't mean there is impulsion in the hind end. The horse can just drop its back and go as fast as it wants. Although it is sometimes easier to have impulsion while going forward doesn't mean that's what impulsion is.
You can not have impulsion w/o forward. You can not have collection w/o impulsion.
I said nothing about 'speed'. In fact I specified what forward actually meant. Let me quote for you: Forward is as much a state of mind and being as it is an action. Moving from point A to point B with a purpose, with motivation, in front of the rider's aids..that is forward.
Also, being "infront of the leg" just means that your horse has come up into your hands and is moving uphill.
No. A horse can be forward and in front of the leg and not yet accepting contact or moving 'uphill'. Forward comes before EVERYTHING else.
The first element on the scale is rhythm. The horse must be forward to work on that. And yet rhythm comes way before moving uphill, or acceptance of contact.
And while we know that all the elements work together and cycle around each other, the fact remains, no forward, no nothing.