I mean you can judge it too fast if alternate is hard to learn and dragging the pick is easy right away. So you assume too fast economy is better. But I have looked everywhere on the internet and the only examples I can find of fast 3 nps scales with strict alternate are a few professionals that have all day to play guitar. Maybe people who only have 2-3 hours at night should use alternate slow/sweep picking fast? Cello/viola/violin... are all tuned to fifth intervals. So that makes easier 4 note per string scales. More notes per string and less "outside" string changes. Everything is easier for the right hand. 3 notes per string is hard to pick fast.