Ice block while diving

[DetectorGuy]

I saw some Ice diving photos from Europe that showed divers pushing the triangle ice block under the ice. The last diver would push the block about half way under the hole and then crawl up on it and out of the hole. The block would be then be slid into the hole the rest of the way from on top. This seems like a completely dangerous way to do things. The tether rope could and would get snagged on this submerged block of ice and possibly pull the block back into the hole trapping the diver. Not to mention if the rope gets snagged on this submerged block the rope tender would not have an accurate sense of where the diver actually is. Has anyone ever used this method of temporarily storing the block of ice underwater? I hope not...