Do you really want to play those notes with your pinky all by itself?
I realize people are divided on this. Some will say that playing one fret per finger is what they do and others like me advocate playing notes with the pinky supported by the ring finger and changing hand position rather than painfully reaching for that upper note with the little finger on its own with the ring finger orphaned, hanging in the air for nothing. Your pinky is your weakest finger. Do you want it to do all that work by itself?
I played a lot of my early years doubling up like you mention or sliding up and using my ring finger. When I really started trying to play faster and clean, I started incorporating my pinky by itself more and more and practiced smooth scales, and guess what; it got strong all on it's own. I can use it just as easily as any other finger now and I don't even think about it anymore. I'm talking I can easily hammer on and pull off with my pinky and it never crosses my mind which finger I'm using. It just takes some time to get there.
This is actually my downfall on guitar though. My fingers are so strong that it slows me down on guitar if that makes any sense. You can barely touch a fret on a guitar and make the note ring. I have to try the light touch approach to speed up. Amazing how little force it takes to fret a guitar.