This can't be correct, my lagometer comes out looking all serrated, any idea why this would happen?

I often miss rails, or get through rails that should be a hit, i.e target standing between doorways, or w/e. Shotguns are often hit and miss, emphasis on miss.

Also, i've got the two most irresponsible users on my network capped to 1mbit down 128k up BETWEEN them, yet i still lag on a 8mbit/384k connection.

Firstly, why is my lagometer jagged? shouldn't it be a straight line?
Secondly, why do c*nts make me lag when they're capped, pretty ridic. Plus i have the best net available to me, apart from getting cybernetic implants and running the server out of my brain.

Thirdly, and most importantly, why would i miss rails that should be hits. Shotgun too, any idea why? I've played at mates houses and they seem to have much more consistent rail rego that i do, and only have approx 5-10 less ping.