Adding sucrose vs. dextrose to paste and when??

Been reading alot and I know " there is more than one way to skin a cat" as my dad always said but the simplist version of mixing paste seems to be adding lemon juice, henna powder, and sugar together will the oil all at once, waiting for dye release, (or waiting for release then adding oil), straining it and filling cones.
Yet...some say to wait on the oil additive until you KNOW you have dye release happening...but just today someone told me this:
1. Mix powder and lemon juice. Wait 12 or so hours.
2. Then add dextrose and oils. Wait maybe 6-8 hours? Naybe fill cones then wait til use 6-8 hours?
3. Then fill cones and use up or freeze.

Please share your methods as to when you add the sugar, sucrose or dextrose? And is SPLeNDA (little yellow sweetner packets, I think its dextrose?) better than white table sugar? How does the Sweet and Lo (little pink packets) figure in? They seem to have other ingredients besides dextrose.
Thanks