Yeah I've had a couple of managers try this. I always tell them my estimate is how long I think it will take take. But if he believes that estimate is incorre

Yeah I've had a couple of managers try this. I always tell them my estimate is how long I think it will take take. But if he believes that estimate is incorrect he's welcome to modify it as he sees fit. (Over e-mail of course). Sometimes they'll modify it, sometimes they won't but at least I won't have to argue about it or get in a situation later where suddenly they pretend like their estimate is my estimate.