Editing minecraft = better pvp

https://www.youtube.com/watch?v=30Lok-eXTRQ
This video shows functions and theres a lot of more
for example: faster eating, bigger hitbox, more range for hitting, speedmine, lower knockback etc.

how to do it:
you have just to edit player sided settings in eclipse

is it possible to fix it?
a lot of polish players using it and destroying pvp servers.