Well, coinjoins don't look like normal transactions, they look like coinjoins. I guess it depends on if you think you can lie to their face and get away with it. A field audit usually goes on for 2-3 years, and they don't really let up. If they think you are lying then it becomes a crimal investigation instead of a financial investigation. Just being honest with them is emotionally exhausting because of how intrusive they are. I'm guessing you've never had IRS agents audit you for all your crypto transactions before. 

 Nope, but it’s probably something that will increase in frequency. Moving business out of the US may be the only option for avoiding it if you want to maintain any privacy.