You are getting a lot of perspectives here. Let me try a different one.
First the instructions. If you are fairly new to this, just use the standard 5% superfat in Soapcalc to make sure your soap is safe, then use the oil and lye amounts that Soapcalc gives you.
Here is the extra credit explanation:
Soapers imagine that they know the amount of caustic needed to saponify their oils, but they don't. They imagine that they know how much unsaponified oil is left in their finished soap, but they don't. The composition and SAP value of oils varies significantly, and caustic typically contains some unknown amount of moisture and impurities that decreases its strength. Unless you go to the trouble of chemically analyzing all your ingredients, the exact result of combining the lye and oils is not really known. You could be using less or more lye than you want.
The "superfat" terminology in Soapcalc is popular but not very appropriate. It is actually a lye discount. When you enter a percentage there, it decreases lye in the recipe by that amount with simple arithmetic. The first reason for this is to help ensure there is some excess of unsaponified oil instead of an excess of lye.
Unsaponified oil in the soap is called superfat. Unlike the lye discount, which is a simple calculation, the superfat is an unknown amount. If you use a lye discount of 5% for instance, there is a good chance of making a soap with some amount of superfat, but it could be closer to 10% or closer to 0%. People who want more unsaponified oil might enter a larger lye discount into Soapcalc, but the amount of superfat will still be a guess.
Let's say you use only palm oil and use its average SAP value with a 5% lye discount. If the palm oil you have on hand has exactly the average SAP value, you'll have a 5% superfat. If your palm oil has a SAP value at the bottom of its typical range, you will have a 1% superfat. If the SAP value is the typical maximum for palm oil, you'll have a 9% superfat. In no case will you have any idea how it worked out.
CP and HP are the same in all those regards. The only difference with HP is that people sometimes reserve one of the oils to add at the end of the process. That helps ensure that any superfat is composed largely or entirely of the selected oil. It's not possible to do that in CP soaping.