It's basically unenforceable. The presumes that unless you tell the security/customs people what's on your laptop, they won't know as none of them have the technical expertise to find it. On the other hand, you put the file in say Dropbox, grab your clean laptop and go. Download before the meeting and wipe after the meeting.
I'm also curious is "exporting" could mean sending malware in a email, etc. from one country to another? Again, how would they enforce this?
It's bafflegab meant to make someone (the sponsors of the legislation) feel important and that they are doing something.