You know what... since your claim seems to run counter to the experience of the majority of iPhone owners, why don't you prove it?
Seriously: design an experiment wherein a jailbroken iPhone and a stock iPhone perform the same tasks. Document the exact software loadout of the jailbroken iPhone. Hell, if you want to get fancy, write down the week numbers. Run the benchmark a couple times and post your results. Some of us will run the same configurations and see if we can't duplicate your results. If we can, and if we find that jailbroken iPhones consistently have worse performance for an agreed-upon set of standard tasks, I will publicly retract every single denial of your "jailbreak == lag" theory.
I'm sure we can find volunteers to help replicate the experiment -- lord knows you've pissed off enough people with your wild claims and accusations of having a "cultist mentality".