I'm 'scarred' from my time in WoT where there basically was a right and wrong way to play maps and informing your team of this at the start was usually met with "who put you in charge?" or something ignorant along those lines.
Lately in WoWs I've been trying the indirect approach and saying "we need to stick together and move to x or y, so which is it?" Fortunately maps really are that simple so it's just about getting folks to sail in the same direction. It seems to work far more than what I saw in WoT but it's hardly perfect.