Yeah, if you read a little further down we worked with the vendor to get them extensive diagnostics and get to the root problem. TL;DR: Lock contention on the CAM table.

"We have worked with our network vendor to provide diagnostic information which led them to discover the root cause for the MAC learning issues. We expect a final fix for this issue within the next week or so and will be deploying a software update to our switches at that time. In the mean time we are closely monitoring our aggregation to access layer capacity and have a workaround process if the problem comes up again."

In terms of network scalability, a properly designed layer 2 topology can scale quite a bit farther than our current needs. This is very much the least disruptive change we could introduce to solve the immediate network problems while we work on the future architecture.