I'll be proving why Ten Shadows shikigami can be amped with CE to increase their output, and hence their strength.  
  
**Kirara's Technique Intro**

To to start this off, the important parts of Kirara's technique that I use for this analysis are:

1. Shikigami and Sorcerer are treated as the same CE, and the one with the highest output gets everything else with the CE pulled towards it.
2. Two star-marked CE objects will be repelled if it is not the next chronological step for that given star; specifically Megumi's Acrux is repelled upon approaching Kirara's Ginan, as he hadn't touched Mimosa yet.

**Two Contrasting Scenarios**

The first instance we see of this technique is Megumi summoning Divine Dog: Totality (dd:t), and it approaches Kirara, only to be repelled as it hasn't followed star-order yet, and also pulled back by Megumi.

We know for certain this first instance has dd:t pulled back to Megumi, not only repelled, as later on she mentions "Like that puppy earlier was drawn to you", referring specifically to this first instance.

Then later, we see Megumi send out dd:t, only to be pulled towards it right after. Now the fact that dd:t was pulled towards him before, yet now he is pulled towards dd:t, means there are only two possible output explanations:

1. Megumi was initially reinforcing himself at first, then stopped reinforcing himself after sending it out again.
2. Megumi reinforcement never changed, but he amped dd:t with more CE after sending him out the second time.

**Why only Scenario 2 is plausible**

The second scenario is much more plausible than the first scenario, as the anime clearly depicts dd:t with a CE veil around itself, which it didn't have the first time, which is used to visually imply outputting CE.

Furthermore, by this point, Megumi doesn't know that output influences who gets pulled towards who, and he explicitly only mentions his reinforcement changing when he needed to guard her attacks, which only occured right at the end of the fight, not in either case of sending out dd:t.

Hence we can assume that Megumi is able to at least increase the CE output of his shikigami, which allows us to make further judgements of other scenarios (i.e. Sukuna). Whilst this evidence is structurally sound alone, it would still be best further supported by other similar instances, like Yuki's Garuda sharing an output with her, and Kenjaku being able to amplify CSM spirits with his own output.

**How this affects Yorozu...**

If the Ten Shadows could not be amped with CE, Yorozu would be scaling in the same relative zone to Megumi's shikigami that Sukuna uses, the same Max Elephant that Reggie was able to hold up. 

Also I'd like to note that during the Yorozu vs Sukuna fight, the narrator mentions Sukuna being able to "compensate" unstable shikigami being weaker by amping them. To be honest, that isn't evidence either way, I can elaborate if someone comments about it, but basically it's just amping them to return to the same baseline output level.

[Serious] How Kirara's CT proves the Ten Shadows can be amped and SAVES Yorozu from being Reggie level fodder...