Fiddler improves Service Response times?

One of the development teams approached me with an interesting issue. The issue description states the response time of a service call is faster by 100% when ever Fiddler is running.  I was requested to suggest if the same performance can be achieved without fiddler.

I took some Network traces  at the client with and with out fiddler and found some interesting observations

Without fiddler, Only 2 TCP connections were used between the client and the server

With Fiddler - there were 4 active parallel TCP connections resulting  faster response time

With the data it is clear more the parallel connections the better the response time. With the issue identified solution is even simpler

By default, we can create only two simultaneous connections to an HTTP server.   This can be increased to avoid a backlog of requests during times of very high transaction volume. It can be done in many ways as given in the link below

https://developer.cybersource.com/library/documentation/dev_guides/Simple_Order_API_Clients/html/Topics/Setting_the_Connection_Limit.htm