I noted that she had moved freely in the first stride or two before the tightness came in and short-circuited her flow. I had not directed pressure towards the mare in my initial request, I had just released her forward. When a horse has been taught that pressure of some kind is always in a request, there is often a spot to work out, when releasing that horse without the pressure. The pressure is still anticipated, but is absent, so in a sense, the expected timing is all off - he is already right and has done what was asked, simply by following a feel of release in the moment. This can leave him wondering where the pressure went, and you might see his normal, but displaced response to that pressure he is expecting, or a slight concern around his sureness that it must be coming.
The mare was in that spot: a little confused about the change in feel and timing. She had instinctively followed a feel and was already right. The normal reference point of a release of pressure marking her correctness was 'missing' - as was the pattern of "wrong" until you find "right" sequence that accompanies it. This actually caused her to be unsure about whether she was right. Since a lack of sureness in her understanding of a request was normally associated with a judicious and therefore predictable increase in pressure, this caused her to stand tight as she anticipated the pattern of pressure. Yet all the while, the pressure anticipated was not forthcoming.
For all these reasons - or particles of feel - it is also characterizes a golden moment in process if the handler can offer the feel and timing to ALLOW it. What does this mean? We have reached a moment in which the horse is right on the line between flight (or fleeing inward) and curiosity about this change in feel and timing. It is a delicate spot, where instinct is heightened. It is also a wide open doorway to that horse and the opportunity to for a connection of a very different kind. We just need to learn how to be invited through that door - through feel.
The common temptation would be to have the so far incomplete circle I had planned drive our next move. I could have done that, as I surely would have at one time in this journey, and she would have made it somehow - BUT I would also have confirmed and built on the established awkward staccato of misunderstandings, manifesting in misinterpreted brace. ANY suggestion that she ought to be doing more (towards that circle I had in mind), no matter the presentation, would have carried a feel of pressure at that moment - and slammed the door closed, by adding to her brace and sending her (in this case) inward, back to a quietly closed state.
The alternative would be to support her sorting through the shift to release her curiosity. If I am able to feel of a horse to achieve this, he/she will invite me right through that door, and I will find myself in that magical spot where we are together in lightness through feel - and it weighs nothing, becaused it is offered and received. A golden moment to be sure, and that is why I call this "The Vein of Gold".