First we need to make a distinction between what I call Commanding vs Controlling influence, (in the book they are listed as indirect and direct influence.).
Basically, Commanding influence is changes that you make in yourself to make you a more influential person. Moving your set point, adjusting the way you look, doing exercises to build confidence, smiling, etc. The idea is that men will give you money and women will swoon (or the other way around) not because you have made them believe that you are a person they want to know and follow the lead of, but because you are a person they want to know and follow the lead of.
For the most part you can go ahead and go nuts with commanding influence as long as what you are doing is making you happier. If you feel you are becoming someone that is fake, than stop and re-examine. You should be so happy about what you are doing that you can be totally up front about your work with those you are trying to influence. I really like Tynans concept that if you are a PUA, you should be able to tell a girl that you have studied PUA tech and make it work for you rather than against you.
Controlling influence is another matter. This is influence aimed at a target with the intent of effecting their mind directly. In "The Sorcerers Secrets" I have a chapter on magical influence. In the beginning of that chapter I make a defense of influencing magic as not being inherently unethical. In a nutshell you cannot not influence people around you by your actions so you may as well be skillful at it. At the end of the chapter I revisit the topic and remind people that while influencing magic may not be unethical, if you use it all the time on everyone you are a probably douchebag. The reason is that if you are always trying to get your point across to others 24/7 than you are never really listening. I am mostly talking about Controlling influence.
But there is more to it than just not using it on everyone all the time. There is a matter of how strong the method is and how ethical your methods are for what you are doing.
It may be appropriate to use some light influence like NLP style anchors or direct energy application on a rebellious teenager, but you don't want to go whole hog and try to dominate him if you want him to grow up healthy and maintain a good relationship. If you are trying to pick up someone at a club, you might want to use slightly stronger methods to get your foot in the door, than back off if you manage to get a second date and start a real relationship. You may want to go even heavier with your boss when trying to get a raise.
In all these cases though, if you go to heavy handed you cross the line from being charming to creepy. You cross the line really really fast. A while ago I posted a link to a blog about someone who hates Tim Ferris because he used some social trickery to get her alone for lunch and talk about his book in hopes of getting a favorable review. His tactics were clearly too heavy handed and while they worked, he left her with a bad taste in her mouth for him and his work. I count that as a fail.
If you want to go full on with your influence, make sure that you do not intend on being friendly with that person in the future. Competing company? Opposition political party? Person suing you? Go ahead and knock them dead with spells, NLP, marketing tech, energy work, and whatever else you have. Let them walk away confused and creeped out at how you got in their heads and made them your bitch.
If it is someone that you want to get into bed, or sell a car to, well that is up to you. If you don't care about repeat business of further dates, than yeah, your tactics will get you what you want for now. But like Tim, they will have the opposite effect later on.
If you are going whole hog influence on your wife, friends, and co-workers, than you are probably not going to succeed for long. You may get what you want in the short term, but in the end being a douchebag will overpower any influence that you may have gained.