Hi Caligirl,
I am a technician in NYC (this is my first post here! :))
How many treatments have you had in total using the YAG? As a technician, I do not double pass the area (personally, I do not think it is safe). If your technician is overlapping properly (about 30% for Candela machines), then there should be no reason to do any double passing.
Without seeing you in person, and if you are a true skintype 4, I’d be hesitant at treating you at 16j on a Candela Alex without giving you a test patch in the area first. Just because you can handle a high YAG setting does not mean you can handle an agressive Alex setting. 16j is NOT the minimum you’d want to do on an 18mm spot size if you are taking the persons’ fitzpatrick into account, as wlel as density, color, thickness of hair and the amount of treatments they have had.
Taking your ethnic background into consideration, it’s important to TP the area first as being a Latina you can pigment if the settings are too high on an Alex.
If you are on a YAG, you should find out the MS (pulse width) that the technician used on you and if it was 5 or 10ms, it should be lowered to 3ms. Hope this helps!!