I wanted to fly from Norwood MA to Montauk, NY, which as a direct flight is 75 nm, as shown below.
I decided to fly IFR but the likelihood of getting a direct routing for a trip of this length is tiny. So I looked up previous routes and found and filed for this one, which is only 77 nm.
But when I called ground for my clearance, I was given this routing.
Not only is it longer (132 nm) including flying past my destination for about 20 nm (adds 40 nm to the trip), much more is over water. So I cancelled IFR and flew VFR.