Earlier quoted context omitted.
A shadow partition would be more effective at bypassing customs. For real boots, you use a copy of grub on a usb dongle. When grub is missing, you boot into a honeypot Windows XP partition that was installed only for that purpose.
No. "Only for that purpose" means that you never use it. This is trivially detected: the OS event logs will report that it hasn't been booted in 6 months, and no files have changed in that time. It's obvious that you haven't been using that system in the time you were out of the country; why did you have it with you? For this to work, you need to actually use the dummy partition for non-sensitive matters -- and be ab…
There is nothing unusual about that.