Both feet flat on the floor when sliding forward and sideways?

you're usually "supposed to" ...generally speaking....you should push off your back toe when you STEP with your jab.
And if you dont step with your jab you can still push your body weight forward behind the punch by digging that back toe "two inches" into the ground as you push

 

theres part truth in this. most of your power comes from the sole of your back foot. i like to throw my straight punch with back foot flat.

i prefer to have my heel off at all times for balance. if you get hit with a shot, the ability to land on your heel gives you a bit of extra 'spring', or give.

 

well, he did say that you shouldnt be flat footed when dancing. you wouldnt be flat footed in this case. if you are happy that the trainer is doing the right thing by you, i would listen to what theyre telling you.
its really not something thats technically right or wrong really. (unlike things like 'keep your elbows in' etc)

like i said, i like flat foot for power. its suits my style.

 

I don't see how it's biomechanically possible to throw a technically correct rear hand punch while having your back foot flat??

 

i roll into the cross. that lifts the foot.
all of my cross' power, timing and speed come from my back foot.

 

na dude forget that "power" crap, everyone thinks they're so powerful...it's all pretty useless if you can't hit your opponent. if you're lifting your back foot off the ground are you throwing your weight onto your lead leg? for a cross

 

no. power is not crap. timing is everything.
fine if you want to do shitty ***gotry 'superman punch' like in mma, where you throw a cross in mid air. bull****.
the best punch, power, timing, everything comes from back foot, not 'falling over' towards your front foot. i throw my weight to my rear leg, not my lead leg.
and trust me, my left cross is my strongest punch. and im not naturally left handed.

 

show me one trainer or video that shows how to throw a cross punch & has any focus on the front foot?

im not going to argue it, its what works for me & has resulted in my best punch. like ive already said, its all personal from fighter to fighter & trainer to trainer.

 

speed kills. what's timing if your slow at getting there? And the falling step is a great way to generate power. I only do it with a cross if im standing southpaw, for some reason Im better able to slip under and come back with a lead hook as i pivot out.

 

the cross is my fastest punch also. im a right handed southpaw, and my straight left is my most complete punch.
seriously, falling over while throwing a punch is DEFINITELY something this is actually technically not correct, sorry.

 

read about jack dempsey's falling step?

 

yep. stepping when jabbing. (we're talking about crosses, not jabbing).
some trainers will tell you to step when jab. some will tell you flat while jabbing. some will tell you step only when double jabbing.

nobody (except for mma cocksucker 'superman' punchers) will throw a cross off balance/ no feet off the ground.

 

the way i throw that cross from southpaw i put my weight on the lead leg because my head is off center and to the right kinda like a slip it makes it easier to pivot out and or avoid oncoming punches.