Splitting currency down like that is not a good answer to the monetary deflation issue, which is why he said he didn't think you understood.

It's not simply the quantity of available currency that is the problem with deflation, it's the appreciating value of currency compared to goods and labour.

Splitting does not resolve the issue of deflation that is that a given unit of value (1 btc, 1000 micro-btc post-split, whatever) increases over time. It doesn't matter what you do to it or how you measure the quantity of value - if that same value is worth more tomorrow than it is today, there is a prevailing negative pressure on spending it and the result is that people will prefer to hold on to the currency rather than exchange it.

The deflation argument is about the disincentive to spend your coin, regardless on how they are denominated.