i use all my folded EO's the same as none, I personally would not use less, they don't SEEM to be harsh or irritating in my soaps, never know the difference other then a stronger scent.
I also tend to use a base note or middle note EO with citrus to help as well as adding clay directly to the EO and then adding scent to soaping process.
I have never did a test with or without clay to see which one held scent longer so I am in no claiming it is fact, but I do it anyway, and mainly because I like clay for its many other benefits like a mild exfoliant and color and detoxifing effects etc etc.
I have however did an experiement with just Citrus EO and one with Citrus and middle/base notes, and they tend to smell citrusy longer.
Something like Lavender/Lemon smelled lemony longer then just Lemon on its own. I don't know why this is or the science behind it.
