So here's an example of a line that uses a lot of root > fifth below. In the video I'm playing it two ways. The first time through I'm using one finger to go between the root and the fifth, second time I'm using two fingers (either 2nd and 3rd, or 3rd and 4th depending on the position). I'm new to fretless. My priority is to play cleanly, smoothly and relaxed. I feel like using two fingers here allows me to play more legato. Using one finger takes less energy but there is always more of a gap between the two notes. I'd like to know what other more experienced players have to say... do I need to build more strength to use two fingers or work on using one finger more smoothly?