I installed an SSD in my 2011 Mac Mini to run alongside the stock 500GB HDD. After carefully reading through a number of tutorials, I used Terminal to merge them into a single "Fusion Drive". I cloned my data back over, and all seems to be running perfectly. I'm seeing a very nice bump in speed in starting up and launching apps, and other disk-intensive activities.
In browsing through various articles and forum posts on the topic, I see some people claiming success doing this with various Mac models, but others claiming that home-brewed Fusion Drives may not actually be migrating data correctly between the SSD and HDD. In particular, this OWC tutorial claims that this ONLY works with a 2012 Mac Mini because "these are the only machines that currently have a version of Disk Utility that can create a Fusion volume". In the comments, the authors further state that
According to our techs, when using any version of Disk Utility other than the one that came with the 2012 Mac mini, it will appear as though you have a Fusion Drive, but it will not behave as such. You would be essentially creating a standard Core Storage volume rather than Fusion.
My question is: is there a way, without buying specialized dignostic software, to verify whether or not the essential "fusion" of data migration is occurring between HDD and SSD?