I'm approaching a year of shooting off trek poles now, and teaching my kids to do it, and....
It's awesome if the ground is halfway soft. Awesome if there's a nice sod or even a halfway decent vegetation covering the ground. But here in the summer when the ground is hard and dry, or at our local flat range where the firing line is hard packed gravel or concrete, trek poles are really hard to work with. Positions that would work in the field won't work on the range because the poles won't grab into the hard dirt.
That's no fault of the position or the poles, just an annoying reality of trying to practice, especially on a commercial range built for comfort over practicality. One thing I've learned is that the shorter the poles are shortened, the steeper each 'leg' has to be, and the better they stay planted on harder ground.