Really only an issue with big beers. I suppose with lagers that have been lagering a long time it might be a good idea as well. For most normal gravity ales it is really not needed, there is still plenty of yeast in suspension when you bottle.
As a side note it's not a bad idea to get into the habit of measuring priming sugar by weight like you do with other ingredients, it is far more consistently accurate as changes in density of the sugar and humidity can effect the actual amount on sugar you are adding when you measure by volume.