"If this, or any other test says your site is slow from a particular location on the net, what can you possibly do about it"

Basically it nails down to reducing the number requests and the roundtrip time per request (aka latency).

- Use a CDN to reduce latency (e.g. cachefly, cloudfront) - Outsource some javascript libraries (e.g. jquery) to google's CDN - Move servers closer to customers.