There is also increased network traffic, more bytes to keep in the caches (RAM?), maybe effectively doubling the amount of data you store (in the worst case) cr

There is also increased network traffic, more bytes to keep in the caches (RAM?), maybe effectively doubling the amount of data you store (in the worst case) creates terrible effects on (some of) your queries and increase latency somewhere in the system and you have to find where... There could be "big" ramifications, it's a pretty interesting thing to think about :)