Why have I been interleaved?

[#1]

Hi, Yesterday I raised a ticket (25025989) asking why my IP profile had been reduced to 4000kbs despite the fact that my connection was extremely stable at its previous level (around 6000kbs). I received a reply stating that:
"having reviewed your account it would appear that your speed problems are being caused by an intermittent connection."
I replied that I hadn't been having any problems with my connection. Consumer support then wrote back to say that:
"we have asked our wholesale broadband suppliers to turn interleaving on on your phone line to try and fix your current broadband problem."
I don't understand why I'm being told I have an unstable connection when it is not the case. How could interleaving help to raise my IP profile? Surely it would only reduce it?
If anyone could give me some clarification on this I would be most grateful.
Simon

[#2]

This may be another classic case of CS not reading the ticket again 
Interleaving is generally turned on on lines which suffer disconnections or loss of signal quality to help stabilise them and keep them connected. It will reduce your max sync rate as a result.
BT's exchanges is very sensitive to even one or two drops of connection sometimes and can up your min SNR value and thus you get a slower sync rate.
If you are convinced you don't have line problem reply saying you don't want the min SNR Raised or interleaving turned on.

[#3]

Hi Simon.
Sorry to hear that you are having problems.
There is a definate reason for the drop in speed and you did suffer short disconnects on 10 and 11 of this month.
I agree that interleaving may not be the necessary approach and indeed the response you got was an automated one from our Faults checker. I have asked one of our dedicated faults guru's to take a look at your problem and he'll provide a greater level of detail in your ticket response.
I'll also have a look at the auto response side of things when I get in tomorrow and solicit some advice from our faults Manager.

[#4]

Thanks for your replies. I have another question - how do you (or the telephone exchange) tell the difference between me deliberately disconnecting my router (as I have habitually done when I turn off the PC), and a disconnect that indicates a fault? I don't want to leave my router on all the time.
Thanks, Simon

[#5]

There's numerous different types of disconnections.  BTs RADIUS server will probably interpret them differently.