I don't think he ever said he had not already bought loads of START.  It is obvious he has duh.  here is a Karl Gray tweet from Feb 28th,

"I've been a net seller of #Bitcoin for the last 12 months, something even bigger (and dare I say more valuable?) in the pipe!"

I also remember a tweet where someone asked if he was buying and he worded it cleverly saying he is "buying now" or something like that.  which could be falsely read as he just started buying but that was never said.  Really it only meant he is buying now (which does not exclude buying previously).  Of course he already loaded up!! I think the StartFund he is creating (if I understand it correctly) is going to be buying soon (not bought yet) and doing lots positive things for Startjoin ecosystem and price.  IMHO Karl sees the potential and knows his personal investment will be worth a fortune and he can near guarantee and most assuredly speed up that process by creating the fund which should draw a lot of attention to Startjoin when project funding increases from his funds giveaways and whatever else he has planned. Simple and perhaps brilliant plan.

Think how easy it will be for us early folks to give 10-20 pounds or dollars worth of start to a project when start is upwards $1.00!!! Of course there will be dumps and price crashes (this is crypto afterall) but to succeed it is all about expanding the user base and getting projects funded.  The projects (which keep getting more interesting) also bring in new faces to crypto. The projects are advertising.  You may have fans, supporters of a project that knew little or were reluctant to get involved in crypto but then they wanted to support say the Mega project or the Chelsea manning project or whatever. It is BEAUTIFUL!