WL 5 appears to update all Data Sets separately; and repeats the updates even if the same symbol is in multiple Data Sets.

WL 4.5 seems to consolidate the symbols of multiple Data Sets and updates the consolidated symbol set once; appearing to provide some efficiency and avoidance of duplication, and better speed.

If the observations above are true and correct, I would think that WL 4.5's method is better, more efficient, faster in this regard.

Are there compellingly superior reasons for WL 5's duplicative method of updating its Data Sets?

QUOTE:
WL 5 appears to update all Data Sets separately; and repeats the updates even if the same symbol is in multiple Data Sets.

Of course no, this is far from reality. How could WL4's update speed be faster if updates are single-threaded?

When performing an "Update all data...":
a) WL goes top down from one registered data provider to another
b) all symbols of a provider are consolidated, no separation;
c) WL5 only updates each symbol one time per each time frame (M1 ... M30 etc ...), in the context of a multi-threaded download.