Up until now, I haven't addressed the issue of those talking about using an "up stroke", and how effective it is. Earlier, AtLarge posed a question that went ignored. His question was very relevant to the discussion.
I just checked something on my table, which is a Valley. Laying the butt of the cue on the rail, and the cue extending out on the table, I wanted to check how high the tip was off the table with a level cue. Level being a straight line down the center of the cue. Center of butt to center of tip.
I placed a striped ball at the tip, and checked where the tip contacts the ob with a level cue. As level as it can be since it stopped by the rail from going any lower. With a level cue, the bottom portion of the tip, which is what will contact the ob, is a little above the miscue limit (the stripe) on the ob.
Therefore, unless one has the butt of the cue out on the table, which would result in a very long reach, (cue has to have the butt at least 4" out on the bed to be able to stroke it), one can not even shoot with a level cue, let alone with the tip raised to create an upstroke. And, even if one could, it would result in a massive miscue.
Just because some pro says something works, doesn't mean that one should automatically believe it. especially when it is so easily checked and proven to be false. There are a ton of myths out there that have no basis in reality.
So, on a pool table, you can't use an upstroke. On a billiard table, I don't know. It has larger balls, and I don't know the height of the rails on those.