You will however have a melee ability that costs 0 focus. If you are healing spec'd and want to throw in some damage, but want to save your focus for healing, then you could toss in a melee attack that costs nothing. Or even if you are dps spec'd but run out of focus, you can still attack with your saber.
Even when healing sabre strike is close to useless, it does extremely low damage. Oh and as a DPS you should never be close enough to an enemy to use a melee attack anyway.