Via William III, Digby.
At the risk of 'teaching my grandmother to suck eggs' let me remind you that, in their Eighty Year War of liberation from Spain, the Dutch became the pre-eminent infantry in Europe, developing a fire discipline for the new firelock that they taught to the world. Gustavus Adolphus acknowledged his debt to the great Maurice of Nassau in this regard. With Dutch William as King of England, it wasn't long before the English infantry saw the Dutch Guards in action at the battle of the Boyne. The new platoon firing of these Dutchmen destroyed the Irish cavalry trying to thrust them back into the river. Soon after that platoon firing was taught to all the English army. I strongly recommend you get David Blackmore's book that I plugged in another post in this thread. Together with Brent Nosworthy's "Anatomy of Victory" it helps to explain the development of fire control and musketry for our period.