Back in 2013 a moron by the name of Luke-Jr ran a stupid pool by the name of Eligius, with crappy pool software called eloipool written in python, and the pool had lots of problem and lots of orphans.

The other major pools didn't.

So the moron decided to make changes that are bad for bitcoin to his crappy pool software to reduce the orphans.
Clearly his programming skills are crap because:
Those changes included (among others):
1) Sending out empty blocks to miners after network block changes ... then later sending out proper work with transactions
2) Reduce his pool limits to only accept 32 transaction per block ... for 5 months.

That first change still exists today in that pool.

I can only guess that the developers at Bitmain followed that example 1) above.

CKPool running on my pool (the part of the pool that -ck wrote - the pool mining engine) doesn't do this.
We always send out transactions with work unless bitcoind has none
(which is probably never - or on the VERY rare occasion for a few seconds when you start bitcoind - which again we rarely ever stop bitcoind)

Thus endeth the factual lesson