People with higher SteemPower have stronger votes. So your example with 1% has a 200$ full vote (100%)meaning he might not want to give the full vote but rather a smaller one.
How was he able to mesure it? Simple; when you get to 500SP or above you will get a voting slider and with SteemitMoreInfo app you will know exactly how much any % of your vote is worth in $$. Check it out.
Thanks you so much for this clarification.