In the text "Karate-Do Kyohan: The Master Text" there is a description of how the rising block should be performed in a basic partner drill format. I think it is on page 225 if anyone has access to a copy.
Here is what a part of the description says, with the main part of interest in bold:
"Defender: Lowering the hips and stepping back with the right foot, execute an upper level rising block with the left arm. The intention here is to hit the opponent's chin or armpit."
Does anyone practice it like this? Personally I have never been taught to do it as the text describes. The version in the text looks like a very effective way to perform the block, and I was thinking that perhaps it was changed in more modern times to make training less dangerous? I'm not too sure, maybe someone more knowledgeable knows about the history?
I would be interested to hear anyone's thoughts on this version of the technique.