"The most efficient fingering" is often subjective. People have different hand sizes, finger lengths, technical strengths and weaknesses.
… the difference is not that great, at least not so great to say the whole process of determining the best fingering is an utterly subjective matter.
I'm not making that argument. All I was doing was reaffirming what I believe you meant this topic to be about; that is, finding the maximally efficient fingering for certain passages of music. I was merely trying to clarify to youngpianist that this topic is not a general discussion about fingering, which is a mistake that I had previously made.
Yes, I observed that it was possible to solve this using two positions. However, I thought it was more comfortable to pivot from the 4 onto a new position (starting with the thumb) rather than the 5. What do you think about that?
What do you think is the trick?
Yes that's it Ranjit. Lelle gave the best fingering. This is from bar 24-26 Minute Waltz from Chopin, quite a famous example.