I think BTC price is manipulated. Al the order books are fake and you need a huge amount of value to move all the important exchanges at the same time. One you did that, you get reactive effect but the timing is important!
i don't think so, it is that they are using bot all over the place, in every exchange, you can use your too, human trading is very rare nowadays
manipulation is there but to a much less extent than before
nowadays there is a lot less manipulation, i think that's mainly due to the fact that traders are wiser. especially when good or bad news pop up and cause a massive price movement. news doesn't move markets anymore. that means that inside trading is less effective.