The debate over long interconnects and short speaker cables vs. the opposite rages on. My opinion is unwavering and counter to the rule of thumb: long speakers cables and short interconnects are best as power amps have a better ability to drive a complex load than does a preamp.
Your mileage may vary and most cable manufacturers will tell you exactly the opposite.
Here’s the deal: what works best in your system? Despite my first statement, I actually do the oppositie in my reference system: long balanced interconnects and short speaker cables. Why? Because that’s the most practical application in my room.
There’s optimum and there’s practical. Either can work, just make sure you optimize the components to fit the situation. A rule of thumb is just something we use as a starting point, not an end dictate.
Do what works.