Verizon DSL - isn't it supposed to be constant?

Over the last week, I have noticed that my download speeds for Verizon DSL are not what they are supposed to be. Heck, that would not be as irritating as what is actually happening. I get the advertised speeds during parts of the day, and 1/2 the advertised speeds during parts of the day. I thought the big advantage of DSL over Cable is that the speed does not fluctuate based on usage.

Experience with Verizon Tech Support has been a little less than stellar (I am being polite). Every guy I contact wants to do a line test and then wants to do a screen share and tweak my computer. Really? How will that help? I don't change anything, but my speed changes. It changes even when none of the computers have been rebooted/shutdown, or the modem recycled.

So, for kicks, I downloaded this app from the Apple App store, from SpeedTest.net. This app is running on my iPod Touch, and I ran tests at various intervals. Not changing anything on my computer(s) or routers, or the Verizon modem.

The results, so far, seem to confirm my suspicion that Verizon is either artificially throttling the speeds during the evening hours, or just has an issue with the local office.

Here is what I have so far [notice the slow speeds yesterday night, switching to fast after midnight and so far today? That is the usual trend] -

Date	Download	Upload	Latency	ServerName
2/27/2010 12:07 PM	2740	659	86	Reston, VA
2/27/2010 8:22 AM	2648	668	87	Reston, VA
2/27/2010 0:52 AM	2699	660	102	Reston, VA
2/26/2010 23:20 PM	1465	659	193	Reston, VA
2/26/2010 22:24 PM	1153	602	84	Washington, DC
2/26/2010 22:01 PM	1442	576	92	Washington, DC

If only I could convince Verizon about this and get them off the focus on tweaking my computer settings.