Menthol with canola for tracheal mites at low temps?

[rmgarvey]

There is a paper (late 1990s) from Univ West Virginia that describes a process of dissolving menthol crystals in canola oil and then using paper towels to soak up the mixture; the towels are placed in the hive and gradually removed by the bees, but in the process, the menthol kills tracheal mites, even down to 45 deg F.  I searched the forum for more recent posts on this and found few, but did glean that the Dummies book used to mention this technique and now (3rd edition) it is not mentioned.  Did this fall into disfavor or was found to be not effective or ????  Thanks

[Michael Bush]

I ask at almost every presentation I give how many people are treating for Tracheal mites.  I seldom get more than one or two hands in a crowd of two hundred.  Then I ask how many people are having issues with tracheal mites now and I never get a hand at all.  As soon as we all quit treating for tracheal mites, the problem went away...

[BeeMaster2]

Same thing will happen when we stop treating for varroa mites.
Jim