What are the issues with the speed calcs?
Let's go through them.
This glances past the nature of the Body Replacement Technique and interprets it as pure speed. Basically the technique 'just works' and there is no consensus among Naruto fans on whether it is a type of teleportation or a temporary speed boost. To understand what I mean when I say that the technique 'just works', lets look at this example:
So how do we interpret this feat? It'll be pretty hard to argue that this is the Animal Path's normal speed, so let's say it is a speed boost. So the Animal Path gave himself a speed boost that allows him to move FTE against Jiraya, freed himself, retrieved a log, placed the log in his old position, and then bailed out. All without Jiraya noticing.
If we are going with the speed interpretation, this is a lot more impressive than Naruto's feat, so are there any plans to calc it?
An other perplexing showing comes from Sakura.
So apparently the supposed speed boost is enough to make Sakura move FTE for the Oto team (but instead of counter attacking she retrieves a log, places it on her old position, and then bails). And per Zaku's understanding of the technique, it also grants Sakura FTE movements mid-air after she has already jumped (i.e. either this is flight or teleportation).
So if we take the speed boost interpretation, this puts serious question on whether we can consider this Combat Speed.
Teleportation is a lot less convoluted explanation and probably the best one, but it is stated that space-time Ninjutsu are rare, and it would make Sasuke's Amenotejikara a lot less unique if every Genin can do a discount version.
The calc also conflicts with an other statement.
It is later stated that the movement speed of Sakura and First Gate Lee while he is tired and weighted (and apparently the average Shinobi too, but this part is retcon-bait) are slower than sound. Sakura is supposedly comparable to base pre-Chunin exam Naruto.
The problem here is that Temari doesn't need to be this fast to do the feat.
At first glance Tayuya's Jutsu gives the impression that it is instantaneous (due to being Genjutsu'd you get paralyzed the instant you hear the sound). However this is not true as there is a shortish time window before the sound Jutsu works, enough for Temari to finish swinging the fan even after the sound went past her.
After Shikamaru started to fall under the Genjutsu, he still had time to throw a kunai. Shikamaru also states that there would be enough time to pin-point her hiding spot at edge of their hearing range from the sound of the flute, but not enough to attack her. He also states that it would be possible to fight her if they had sensory abilities like Neji and Kiba (if he is talking about prep, he could just bring ear-plugs).
We can argue that Temari swatting the sound before it reaches her is the most reasonable interpretation. But even if we grant this, this interpretation also needs to be supported by comparable feats rather than being something conclusive.
The issue is the type of explosion. As mentioned in
the link included in the calculation page, explosives can be classified into
high explosives like TNT and
low explosives like gunpowder. Low explosives like gunpowder are far slower (around Subsonic+ to Supersonic).
Gunpowder (likely the historic inspiration for the Explosive Tags) is explicitly used by high level Shinobi as a tool.
Explosive Tags fits the characteristics of low explosives better since shockwaves are not associated with them, so they are missing the main characteristic of detonations.
This makes the final result of the calc a very high-end when it would be more accurate to take a lower one.