Caffeine actually works to constrict blood vessels, so for an organ like your cock that depends on having maximum blood flow, it stands to reason that too much caffeine is counter productive to your PE goals.
I have been drinking coffee and colas for years and although I had contemplated giving it up, I had convinced myself I couldn’t live without caffeine. Well, recently, due to other circumstances concerning my health I decided it was in my best interests to eliminate caffeine altogether from my diet. I switched to decaffeinated coffee and stopped the colas. I thought I was going to have a lot of trouble, especially waking up in the morning and staying awake throughout the day without my periodic coffee breaks, but you know what happened? I find I feel much better now without the caffeine and actually am more alert in the morning and throughout the day without any caffeine in my system. I used to have a lot of anxiety and that is now completely gone too.
So, if you think you can’t give up caffeine because you depend on it so much to keep you alert, I think you should seriously consider giving it up. If your experience is anything like mine, you will find yourself more alert and feeling better than ever. You might even end up with a better flaccid hang and larger erection too. :)
A little warning though. Since you consume so much, you might want to taper off gradually as going cold turkey might lead to some caffeine withdrawal symptoms like headaches. Once you have finally quit the stuff, you won’t miss it at all. You will probably be glad you did.