I'm still wanting to buy more

We're holding for the long run

I've had success selling and then buying back. I've added 30% to my holdings so far.
Good luck with that. All it takes is one spurt upwards and you will be left in the dust and your theoretical 30% will be long gone.
No it won't. I have 30% more KDC now than I did before. Besides, I don't throw it all in at once. That'd be silly. I go in with only 5-10% of my total holdings.
I've tried your tactic many. many times before. I've sold and re-bought at 100% profit only to find out the next time I thought I was selling at the high, it shot right past me 10x. My lesson? Trying to sell and re-buy when it dips only works with established coins. Coins that are still at ground floor level like Klondike, can shoot up 10x in a matter of hours. Yes, you can pat yourself on the back because you guessed right this time, but I guarantee you, you will try it again and it will shoot right past you and you will have to buy back at 100% over what you sold for, negating anything you made. I've done this myself, sold and when it doubled in price, refused to buy back in out of stubbornness, only to see it go back up 10x more. My new strategy is to buy and keep buying on dips and accumulate until I feel it has reached market size. Of course, I only do that with coins that have great dev support and Klondike has one of the best from what I can tell.
Plus, you are obviously BS'ing. If you sold only 5-10% of you holdings, and sold and re-bought how in the world did you add 30% to your total holdings. I'm not a math genius but something seems off. LOL