Saylor created himself an image of a true Bitcoin believer who is in for the tech and will hodl forever, but remember that it costs him nothing to write posts on twitter, and some 5 years ago he was a Bitcoin skeptic. He changed his opinion because he saw opportunity for profit, and if Bitcoin starts performing poorly, he could easily dump it and look for new investment opportunities. I won't even be surprised if one day he turns into an altcoin shill - maybe he'll use the trust he build to launch his coin or promote someone's coin for a decent chunk of premine.