I have a hard time believing that the 'priesthood leaders' are actually making the assignment, but rather giving general direction to allow appropriate access to the appropriate individuals based on their callings and handbook assignments. When a question arises that might be ambiguous, I can see that going up for a decision. The current
https://leader.lds.org grants access to Stake Executive Secretaries access to Clerk areas of responsibilities, according to tradition, assignment and the handbook. However, I can see where some in the department might say, well in my stake the ExecSec does that and it gets written into code because nobody else has that experience.
The reason I believe this is that it takes very little time during the beta cycles to make changes like that as we notice them as a community, however, after something goes live.... it takes a very long time, in fact, programmers would avoid going back to make changes by providing interesting justifications for why it's there rather than run it up the chain... Those decisions take a long time.
Again, by way of observation and deduction only... the above may not reflect reality at all.
“A long habit of not thinking a thing wrong, gives it a superficial appearance of being right, and raises at first a formidable outcry in defense of custom.”
― Thomas Paine, Common Sense