When it comes to using backhand motions...

Due to the lack of protection on the side of boxing gloves, backhands are not legal for use in the ring. This is the main reason why they are not incorporated in boxing training. If you ar exploring the self-defense aspects of boxing, it would go without saying that the backhand/hammerfist/forearm would be an excellent addition to one's self-defense toolkit. The reason is fairly obvious. The provides additional setup tools with the lead hand and also provide the lead hand with much needed knockout power. This is no minor benefit. A knockout will end a fight....period. So why would anyone avoid adding them to their skill sets? Well, there are a number of reasons. Some people are ideologues promoting beliefs and agendas. Others are marketers that will avoid tipping their hat to anything their system doesn't sell. Some are just followers that want to see someone else do it first rather than having the common sense to know that waiting for someone else to do something first is flat out idiotic.

And so on....

Ultimately, if you want to develop your ability to strike then you need to develop your striking tools to their best and most efficient manner. This means you have to keep you eyes wide open for what can be beneficial.