Hands on hours and class size, mostly. Ask how many students there are per instructor and how much of the course is spent practicing on real faces rather than watching a screen. A certificate mill will dodge that question or answer it in marketing language. The other tell is whether any support exists after the course ends, because the first month back at work is where technique quietly falls apart. A friend of ours went through
Senso Academy in Manhattan and came back with something she could genuinely put on her menu, small group, real practice time. Have your wife ask what the week actually looks like, some programs are intense enough that working around existing clients gets difficult.