Keep in mind, squirrels are extremely territorial. The two or three you see in your backyard are actually keeping out the dozens that want to enter. Removing the dominant squirrels from your backyard, by any method, will only create a vacuum that will constantly be filled. I personally know of one customer who traps and moves his squirrels. He spray paints the tails to be sure they do not come back from where he drives them. After two years, he is up to 75 squirrels......and still counting! But, he is having fun, so we laugh about it.
If I told you I could show you how to win 95% of the time at Las Vegas, would you go and gamble! Of course you would! Yet, for some people, keeping squirrels off their feeders 95% of the time is not enough. It is too bad, because backyard bird feeding is the easiest hobby to enjoy from the comfort of your own easy chair. Rain or shine, wild birds entertain us all.