I notice that the trend in bass fishing is using 7'6 and up rods for punching mats. Does anybody use shorter rods, say 7'-7'4", for punching? If not, why not?

Generally people use a longer rod to get a better line angle when working a bait underneath the mats. Shallower line angle makes for less friction. Also helps with getting longer pitches from the boat.

https://youtu.be/WJntvB0foN4

 

go to 3 minute mark

I've done it plenty of time with a 7'3 with no real issues

My punching rod is 7'4", my fliping rod is 7'9", 2 different techniques..No reason that I can see why a 7' rd would't work, if it had the specs. for your conditions.

*Would you punch with a 7'H/F action bait cast rod ? I have a Veritas 7' H/F bait cast rod I use for as a Biffle Bug rig to aid in getting that aggressive , non delay deflection off of rocks which this stiff rod provides . Just considered a 7' punching rod being a bit of a disadvantage based on only 7' length ?

It all boils down to what is comfortable for you to use. Yes a longer rod will give you a bit of an advantage but if your not comfortably in control of that rod then it's moot. I'm only 5'9 but I have long arms. I can punch with a 7'6 with no problem. I've done it in a pinch with 7 foot rods and was just fine.