The word "tanker" was evocative, I wouldn't get hung up on it.

All I was saying was that physical stores of value increase in awkwardness (principally through weight and volume) when you increase their number, not so for digital.

Challenges in movement of large sums of gold: http://blogs.reuters.com/felix-salmon/2011/08/23/how-to-get-...

Here's what $300 Billion in gold looks like: http://www.celebritynetworth.com/articles/entertainment-arti...

(Note that it would be harder to transport, than, say, the amount of gold one can fit in a pocket.)