Performing An "Upwards Corner Clip"

I put quotes around the title is because the trick in which is done that appears to be an upwards corner clip, but is actually in fact a more difficult variant of a very easy trick: a block clip.

So, what is a block clip?  Well, if the player manages to be on yoshi, and be big, there is a "gap" between their hitboxes.  The gap happens to be ~2 pixels large, and although that number may seem small, that means you have 32 possible different ways of clipping a block from its bottom.
To easily perform a block clip, you can enter donut secret 1, where all that is required is swimming into the bottom right hand corner of a block, aligning yoshi's neck with the corner.  It can also be done from the left side, but it is a lot more precise.

The trick on land is more precise, but still quite easy to perform from the right.

From the left is where the "upwards corner clip" gets its name.  When you are at max speed, you can block clip a block from its left side.  The only way to do so is to gain speed in the air while you are clipping the block at max speed.  It does not require a specific speed, just one that is large enough to shove you through the block.

Jumping like this will allow me to hold down B on one of a couple given frames, and gain height to enter the block and pass through it.  Note that a block clip requires you to be at the block's position and have a y position that is 36 or 37 pixels above the theoretical bottom, so now the trick has become a bit more difficult.

My speed is not 49 here, illustrating that a speed of 49 is not needed in this trick.

SMV Used For This Example