The video below displays a glitch by which a player with jump boost 3 ends up standing on the second block down in a stack consistently through the holding down of the forward key, jump key, and sprint key simultaneously on a pattern of stacks seperated by one block and taking the shape of 3 x 3 structures with a surface superior to the line two blocks above the structures. Upon encountering the glitch, rapid jerky "jumps" occur until you release the jump key. Then it appears that the player is floating adjacent to the stack. In reality, the player is stood on the middle block.

See this video: https://drive.google.com/file/d/0Bx7E5slZlf3oUHV1YUU0UHZJM2c/edit?usp=sharing.