What is the best way to advance against the enemy with infantry?

Quickly move two hexes to get right next to them; no attack this turn, but stronger attack next turn?

or

Move one hex, and attack; but giving them more time to attack you?

Depends on the scenario? 

For example, in Pushing through Caen, the Allies only have three bridges available to cross the Orne River.  They must cross it as quickly as possible to get all their troops into fighting positions; pausing to attack while still on the bridge will just jam up your forces, and prevent a more effective attack later.  Much better in this case, to simply pour across the bridges with as many troops as you can.  You may expect 50% casualties, [ “I can live with those odds.” ~Simpsons ] but once across, you will have the mobility to overwhelm the enemy and achieve your objectives.

On the other hand, there are other times, when you must simply move one hex, attack; move one more hex, and attack again. 

Does anyone have some hard and fast principles they follow, to make this decision of Quick Placement or Slow Attacking Advance?