If i recall Dinqua's tutorial shows him removing the carbs to do it. IF i recall that is, but i could swear i remember that. And that would indeed make for that huge time difference. You don't need to remove them and i think the reason he probably did is so he could take shots of the jets for nhis webpage cuz ther'd be no way to take pics easily with the carbs on.
i've done it a number of times and it never takes more than 20 min/Half hour at the most. needles take even less unless i drop a shim in the slide and have trouble getting it out. look at it this way.....loose3n a screw on the carb to drain then bowl, then take off 4 screws and your there. it would only take about 2 minutes if not for the trouble of removing the screws in such a tight area. thats why you really MUST get those allen head screws when you first do it or subsequent times will be much tougher.And if you have small hans it might even take less time. But in any case 2-1/2 hours is enough to rejett many times !