That's correct.  It's important to understand the tax brackets on long term capital gains.  The first $47,000 of long term capital gains (in the US) is taxed at 0%.  So by selling that amount of bitcoin, you realize a gain, but it's a 0% taxed gain.  Then when you buy back, your cost basis is set to the new purchase price.  When you eventually sell you are taxed from the new tax basis.

It's a way to protecting $47,000 a year from taxes, every year.
 

 that is smart alright, and there is no custodial business involved either, except the minimum required time the coins are on an exchange, so win-win. 

 If you are worried about the exchange risk, then do smaller amounts, it won't matter.  Move $4700 over 10 times if you want.