The thing is it has been a blanket absolute statement made here many times. This information could confuse people that are starting on there learning curve. Besides as long as he uses a BMS that uses relays instead of FET control. And as long as the relays are appropriate, I see no issue with this.
"It is an inexpensive Chinese BMS from LLT. However, I did check the cell voltages reported by the bms against a Fluke dvm and they were within a mV or two. The bms controls charge directly, and discharge using a relay configuration."
I would be more worried about "It is an inexpensive Chinese BMS" You mileage may vary .