Well, dont think that they will be needing more of the knowledge like a swing trader will invariably do. But a scalper trader will be glued to the market chart or his/her monitor scream in other to be at alert when the market is becoming volatile so as to take full advantages.
That point is also right. Scalpers don't need to analyse any market. When price get down they buy and when they see little bit of increase at price they sell that. This trading stays for few seconds. So they can do many tradings in a day and a good amount of profit.