Downloads affecting speed.... Traffic Management?

[#1]

Here's a question for you based on a comment I received...
Why would large downloads over my ADSL connection during the day affect my broadband speed and latency in the evening?
also given that I pay for the Pro add-on, which I am not even sure is adding any value anymore given the traffic management effects I am experiencing.

[#2]

Hey Ebdenma,
I have read the fault ticket for you. Adam is not implying that downloading heavily during the day would impact the evening. During the short period of time when you downloaded 6GB of data this is consuming bandwidth available to you. During this time if you performed a speedtest you would only see the bandwidth remaining to you while the download is occuring not at a seperate time. Uploading can also have the same impact on your downstream speed
Hope that helps
Twills.