Apples and oranges. If you reduce your file size to 4KB you'll be comparing apples with apples. The setup time of the connection counts dis-proportionally high for small transfers and the goal wasn't a high transfer rate but a short time to load. For a high transfer rate you should make your pages as large as you can, they will take a long time to transfer but the rate will be close to the rate of the slowest link in the chain.

This is also why you can't test available bandwidth reliably with a short transfer.