It would take great statemanship but it is still possible to allow a peaceful march for Malaysians.
The police are well prepared and well-equipped to uphold the laws; whether it is for crowd control or rabble rousers and with so many deployed according to this malaysiakini report I am confident they can still save the situation for the PM.
There is no doubt that the authorities can suppress and disperse all the protesters but if one analyses the situation carefully and thoughtfully, it may result in the conclusion of "Winning the Battle but Losing the War" for the authorities.
I am sure there are still some people in authority who know this in their own hearts. As happened elsewhere in the world, once the general population decides that a system needs change, no amount of force can resist that change for it is only a question of time.
The situation can still be saved if the police grant the permit and then deploy their forces to escort the marches in a peaceful and orderly manner.
Otherwise there will be mayhem on the streets and surely no one wants that. It would be a LOSE-LOSE situation.