I have one with the hole. The funny thing is I found it at a farm sale. It looks well done like yours but I honestly couldn’t say if it’s factory or farm mod! I believe I posted it somewhere here.
you would think but i doubt it. lay a chunk of structural tube, not pipe on the ground. i bet you can jump up and down on it all day without damaging it. pounding on it with a block of wood may not even hurt it. i suppose you could flatten it with hammer but hammers are a no-no anyway.
the stress is always greatest near the head and less the farther one gets from it.