Yes, I learned this early! I’ve created a little script with Power Automate Desktop that has some intelligence so that it only writes a single plot to a single disk at once. All plotters can then saturate the network cause they are all writing to different disks on the farmer.
Today I’m getting a 10gbs SFP+ card for the harvester which should directly connect to the back of the HP blade chassis in the 10gbs SFP+ switch. Ideally, though, the SAS controller I’m getting next week should allow me to connect the blades directly to the SC200 array, allowing me to use the internal 10gbs ports between all the blades to communicate. Each blade actually has 2 internal 10gbs ports, so the blade servers have 20gbs connectivity between them built-in! 
That’s why I want to get the farmer blade directly connected to the SC200 array. The plotter blades would then have 20gbs connectivity to the farmer blade and it would be pretty tough to saturate that - then I’ll be back to raw disk write speeds I think (~150-200 MB/s). I think that at that speed, disk writes should stay ahead of 15 minute Bladebit plots but we’ll see!