HTTP Parallel Connections is 6, but why Transaction Response time is always sum of individual request response times.

In Population HTTP Parallel Connections set to 6, One Transaction has one Page and 10 Requests (http and non http) but Transaction Response time is always the sum of 10 requests fired or grater than sum.
Total response time for that page should be less than sum of time taken for individual requests of a page if parallel connections are set.