I think that most of the people are focosing to develop slow maximal speed in boxing and forgeting the much more important things such as strenght and endurance of balancing muscles. For exampel if you can squat 600 lbrs that alone counts for nothing in wrestling beacause when you are not in the same position as squating your stabilisation muscles will be much more weeker than this from an experienced wrestler... The power in the punch in boxing come not from the maximal power (wich come 0.5 s latter after the begin of the movement)
but from the proper distribution of your own weight. If you see Joe louis foe example, he is not very big or powerful but he is devastating puncher and is know for his BALANCE! Thats why i think such exercise as the evaluation line from Kenny Weldon

youtube.com/watch?v=r6h7BpjKviw&feature=PlayList&p=F337A4325F6 804AB&index=0&playnext=1

are much more important for boxing.


And if you want to learn something for power and atheletik performance,
read something from a real master... and not some selfproclaimt guru!
weightlifting.informe.com/ivan-abajiev-training-lecture-dt186.html
everything2.com/index.pl?node_id=1858480
You can find alot of materials from Ivan Abadjiev.