While a cool idea I can see two practical flaws (Ignoring the downsides of a JDM ISF as the upsides pretty much cancel each other out) at least under my understanding of the law.
Firstly, if he brought it back and then sold it to you at market value, that would exceed his personal tax allowance for the year, so he (meaning you) would need to pay tax on the remainder of the value (and he would also have the inconvenience of having zero tax allowance for the rest of the year.
If he sold it to you for considerably less than market value, then ISF's aren't going to go down in value so if you ever sold it on you would be on the hook for tax (or a considerable hit to your tax allowance) on the apparent profit made.
I could be understanding it wrong, and obviously the point was made more for comedy than an actual scheme suggestion 😛