Carolyn Steedman, “Servants and their relationship to the unconscious”, Journal of British Studies, 42 (2003).
The immense effort of legal, political, and philosophical thinking devoted to the question of service in the eighteenth century is some measure of an anxiety of the employing classes, one that was perhaps managed by masters and mistresses through a routine and ritualized moaning about their household servants.  …
Emulation theory was elaborated for the main part out of eighteenth-century employers’ routine condemnation of their servants’ supposed habit of copying the manners, and behavior, and above all, the dress of their betters, revealing to their masters and mistresses their true desire to be like them. … A theory that had little reference to lived experience in the eighteenth century appears to have framed much historical explanation of its social behavior… there is very little evidence that it was a practice among servants, rather than an elaborate anxiety of employers, that expressed the hope that the servants might be doing just that: watching them, their betters; knowing them, copying them. 
Take that, Neil McKendrick.
(Thanks to Rob for the tip-off to an article I should have noticed ages ago.)