My understanding is that with higher limit values you may end up doing lots of random I/O (for each granule the order in which you read it would be much less pr

My understanding is that with higher limit values you may end up doing lots of random I/O (for each granule the order in which you read it would be much less predictable than when ClickHouse normally reads it sequentially), essentially one I/O operation per LIMIT value. So larger default values would only be beneficial in pathological examples given in the article, but much less so in "real world".