Demi, I view a pony trot as a trot that shuffles and is under-powered and the stride is short as a result of that. A lot of time, those types of trots don't have a clear rhythm. Pony trot usually has a negative connotation.
The Podjahsky passage reads as such:
While the best way to relax the horse and loosen his muscles is by a steady shortened trot, the rider sitting with the reins as long as possible, this exercise will be effective only if the horse trots with short and relaxed steps. Should he begin to drag his hindquarters out of laziness, the rider should insist on increased action of the hindquarters by riding energetically forward, though he must not cause tension by doing this. After a short period at the increased pace, he should return to the shortened steps until the horse executes them in a completely relaxed manner and gives himself up to the will of his rider. However, it is not so simple to achieve these short relaxing steps, which are necessary to improve balance, because the horse will always prefer the walk to the strenuous shortened trot.
The steps of this relaxing trot should be as short as possible. Their chief object is to maintain an even tempo and a regular light contact with long reins. If the horse moves in this way, he must arch and swing his back with rhythm. This attitude should be maintained when riding circles and turns and when making transitions to the walk and again to the trot. Then the relaxed horse will go forward with energetic steps upon the increased influence of the rider's legs and will strike off into canter smoothly and without increasing the contact or changing the rhythm.
So, IMO based on Podjahsky's description, that trot is not a pony trot at all, it is still energetic and forward, just shortened so the horse is not pushed out of balance or over tempo, which would cause tension. Any hint of laziness from behind, the horse goes forward. He says that working in this shortened stride is strenuous, so I don't believe it's just a slowed down version of a trot. It's more of a school trot - which I think an earlier poster mentioned. Yours seems to be closer to a true working trot, but we also don't know what gears your horse has in his trot.
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