This is not new.. Bunnyhopping means synchronizing yourself perfectly, press W, reach the highest speed, jump with A/D, and immediatley when you hit the ground, jump again with A/D, and so on..
Most call a 'bunnyhop script' binding MWHEELUP or/and MWHEELDOWN +jump to be easier for them to get synchronized..
And for those who ask" is it undetectable VAC, VOIPlay etc... You cannot get banned for using scripts... Only not allowed on International Competitions and I doubt you participate there ;))