Vmware and DX extended drive counts to conservative?

We have repeatedely read over the vmware requirements for DiskXtender Windows.

4 vm's per server, 4 extended drives each max.

We migrate large sites from clusters that have DX and 10+ extended drives on each to vmware all the time. In the best practices it is telling me that no more than 4 drives for each vm for a total of 16 drives per ESX host.

You mean to tell me that for a physical server running 12 extended drives in DiskXtender, i will have to break it up into 3 virtual servers with 4 drives each? Why not 1 virtual server with 12 drives (as long as it is under the 16 total drive limit)? What is the difference, logic, and data behind this if i am reading this correctly.

Someone please provide clarification on the matter as this is impacting our business line.

Thanks,

Russ