But it's there, as I understand it, mainly to combine multiple logical packets over a short human sized time scale. By its nature it also prevents fragmenting

But it's there, as I understand it, mainly to combine multiple logical packets over a short human sized time scale. By its nature it also prevents fragmenting poorly written logical packets. But you could also do this as a separate level of protection. Say a 5ms delay on any write without a flush, any further write resets the delay, up until a maximum of 20ms. This would seem to reign in the worst of the behavior - developers not realizing they're sending multiple packets - without adding a large delay to developers using the system properly but not flushing. And since the penalty is much less, it would be less likely to be turned off aggressively, see the Go example in sibling comments. If the goal is to hand training wheels to developers of shitty apps, it's pretty important they actually use them.