I think a lot of the merit of this strategy is realizing equity. Going back to Tyler Forrester's video where he dissected options for aq oop on a low dry board, something like 873r we see that we have a lot of equity but neither a standard c bet or check call were profitable options. With a wide and small c bet range we can protect these hands and arguably realize equity with a large part of our range. Sauce, since that video, has used this betsize in similar spots oop. 

With an uncapped range we can still apply pressure on later streets as well as protect ourselves from overbets.

Kanu is just sick at bet sizings. Remember some hands against Phil...

I don't think it is even close to just a 'preference'. In HU matches small bets (at earlier streets most) works pretty ok, specially against polarized ranges. In this hand, my vision is that the bet sizing is just perfect OTR (all the way he played, actually). He manipulates his bet sizing to match all Kx (K9+/K7) hands and gets away cheaply when shoved on by full houses, since the other player can't shove Qx that is not a full house. 

Also, all Kx hands wins against his Adx bluffs, so it is not weak enough to turn into a bluff and oop is with some frequency betting Qx OTR, so the target is pretty clear and to attack it properly he should go small to increase MDF enough to make Kx a profitable call. 

But I will just let GT/Sauce/Phil do the talking here :D

I think a lot of the merit of this strategy is realizing equity.

Take the extreme example of this strategy- the fish who min-bets every street.  The solution to that seems to be just treat it as a check and act accordingly.  

On the other hand is the player who bets a committing amount on every flop.  Then you just treat them as all-in and act accordingly.

Playing more frequent bets but using smaller sizing seems like a useful tool that's getting worked out as the game continues to evolve.  Kind of like 3-betting.  

I also don't see why you can't just raise a wider range for value against the smaller bet-sizing.

It's not like you would end up losing more money to better hands, but you deny them equity.  

For example, let's say I raise TT UTG and get called by BTN.

Flop: K69r

This would seem like a hand that wants to get it's equity, but when you start betting this hand, then depending on the amount of other hands like it that you are betting, what prevents me from just taking the hands that I would have played until (or through) the river with and start raising the flop with them, bet turn, and check back river (or bet)?

There's more to that example, but that would be my general idea in thinking about it.

It seems like such a thing would be heavily dependent on the board texture.