I don't think that is quite right. If your usage is over the limit, they said they would throttle you, but only on busy towers. Moving around has nothing to do with it, unless he is just having the good fortune of always being on towers that are not busy. That is if throttling is happening.My understanding of Verizon's original throttling plan was to throttle you on the particular tower in which you were using the majority of your data. (Until your next billing cycle) So in your case, (since you're traveling), your usage is spread out across multiple towers, in which case you're not putting up any "red flags" so to speak.
In my case, the majority of my usage is at home or work.
(We should probably move this discussion to the Verizon unlimited thread, being that we've completely derailed the OP) lol