I'm coming to the steady conclusion that you play almost exclusively on Bronze. Most Vanguard tactics you mention tend to go out the window on the higher difficulties. The rush-smash technique may work throughout Bronze, but it won't help you much on silver once you begin running into the barrier'd enemies. Forget gold - everything will destroy you faster than your shield can recharge even if you have Perk 6-2 of BC.
I play them all. Bronze I go for when I run out of supplies and need to stack up. I roughly play 1/4 matches in Bronze, 2/4 in Silver and 1/4 in Gold.
Of course in Gold I don't go charging alone, nor I go charging at too large stacks. I stick with the team and operate as a support trooper.
EDIT: fought three fights in Silver - "rush-smash" works as usual
