Tesco misinformation and bs

I've been using speedtest.net for 6months since I switched supplier from SKY to Tescobroadband, since the beginning of March speedtest says my speed has dropped from a consistent 6.5mbps to 3.5mbps. So I wrote to Tesco, this was their reply... I'd like some thoughts on this please, as I think it's misinformation and bs...

'From performing a quick test of your services, I can see that your speeds should be at least 5Mbps and are currently achieving 6Mbps. In light of this, we would realistically expect you to receive in the region of 5.5Mbps. At times of high traffic, for example in the evenings, it is normal for this speed to reduce. Speed test websites are highly inaccurate however and will not always display a correct reading.
The most accurate way of testing your speed is to download a file and note down the file transfer rate. I can then convert this into a speed for you. For example: If you are downloading a file and it is transferring at a rate of 100KBp/s, this means your speed is running at 1Mbps.
I hope this helps. If you require any further assistance please feel free to contact me again.

5.5Mbps would be a file download speed of 704KB/s but that depends where you are downloading from.

Seems that they are admitting evening slow downs during periods of high traffic volumes but not giving you a specific minimum speed.

All you can do is check your router stats for the downstream sync speed and if throughput speeds are significantly lower than that and are inadequate then change to another ISP.

To say speed test sites can be inaccurate is true, they can be, but so can file downloads with caching and other issues.

Our tester at http://www.thinkbroadband.com/speedtest.html now gives you a graph of the throughput during the test, and uses a single thread (like a download) and multiple threads to flood a connection. The graphs if nice flat lines show a good connection, a wobbly set of lines suggests issues.

Registered speed test uers can also record data and export it for plotting of graphs.

Are you speeds varying across the day, e.g. fast around breakfast but slow in the evenings?