Customize group, strange behaviour of group org export latex

[Rasmus Rempling <4004aa@gmail.com>]

Hello,

I have a question about latex export option and its customization.

If I browse the org export latex group directly after opening emacs and 
a .org file the list only give Option Org Export and it looks like this 
(observe that I have not done latex export yet:
    | [ ]-- Group Org Export XML
     | [-]-\ Group Org Export LaTeX
     |  |  |--- Option Org Latex Default Packages Alist
     |  |  |--- Option Org Latex Packages Alist
     |  |  |--- Option Org Export With Tex Macros
     |  |  |--- Option Org Export With Latex Fragments
     |  |  |--- Option Org Export Latex Default Class
     |  |  |--- Option Org Export Latex Classes
     |  |  |--- Option Org Export Latex Emphasis Alist
     |  |  |--- Option Org Export Latex Title Command
     |  |  |--- Option Org Export Latex Import Inbuffer Stuff
     |  |  |--- Option Org Export Latex Date Format
     |  |  |--- Option Org Export Latex Todo Keyword Markup
     |  |  |--- Option Org Export Latex Timestamp Markup
     |  |  |--- Option Org Export Latex Timestamp Keyword Markup
     |  |  |--- Option Org Export Latex Tables Verbatim
     |  |  |--- Option Org Export Latex Tables Centered
     |  |  |--- Option Org Export Latex Tables Column Borders
     |  |  |--- Option Org Export Latex Low Levels
     |  |  |--- Option Org Export Latex List Parameters
     |  |  |--- Option Org Export Latex Verbatim Wrap
     |  |  |--- Option Org Export Latex Listings
     |  |  |--- Option Org Export Latex Listings Langs
     |  |  |--- Option Org Export Latex Remove From Headlines
     |  |  |--- Option Org Export Latex Image Default Option
     |  |  |--- Option Org Export Latex Inline Image Extensions
     |  |  |--- Option Org Export Latex Coding System
     |  | [-]-\ Group Org Export LaTeX
     |  |  |  `--- Option Org Export Pdf Remove Logfiles
     |  |  `--- Option Org Latex To Pdf Process
     | [-]-\ Group Org Export LaTeX
     |  |  `--- Option Org Export Pdf Remove Logfiles
     | [+]-- Group Org Export ASCII

However, if I do one latex export, a group of Option Org Latex Classes 
is added to the list, then the list looks like this:

     | [ ]-- Group Org Export XML
     | [-]-\ Group Org Export LaTeX
     |  |  |--- Option Org Latex Default Packages Alist
     |  |  |--- Option Org Latex Packages Alist
     |  |  |--- Option Org Export With Tex Macros
     |  |  |--- Option Org Export With Latex Fragments
     |  |  |--- Option Org Export Latex Default Class
     |  |  |--- Option Org Export Latex Classes
     |  |  |--- Option Org Export Latex Emphasis Alist
     |  |  |--- Option Org Export Latex Title Command
     |  |  |--- Option Org Export Latex Import Inbuffer Stuff
     |  |  |--- Option Org Export Latex Date Format
     |  |  |--- Option Org Export Latex Todo Keyword Markup
     |  |  |--- Option Org Export Latex Timestamp Markup
     |  |  |--- Option Org Export Latex Timestamp Keyword Markup
     |  |  |--- Option Org Export Latex Tables Verbatim
     |  |  |--- Option Org Export Latex Tables Centered
     |  |  |--- Option Org Export Latex Tables Column Borders
     |  |  |--- Option Org Export Latex Low Levels
     |  |  |--- Option Org Export Latex List Parameters
     |  |  |--- Option Org Export Latex Verbatim Wrap
     |  |  |--- Option Org Export Latex Listings
     |  |  |--- Option Org Export Latex Listings Langs
     |  |  |--- Option Org Export Latex Remove From Headlines
     |  |  |--- Option Org Export Latex Image Default Option
     |  |  |--- Option Org Export Latex Inline Image Extensions
     |  |  |--- Option Org Export Latex Coding System
     |  | [+]-- Group Org Export LaTeX
     |  |  |--- Option Org Latex To Pdf Process
     |  |  |--- Option Org Latex Default Class
     |  |  |--- Option Org Latex Classes
     |  |  |--- Option Org Latex Inputenc Alist
     |  |  |--- Option Org Latex Title Command
     |  |  |--- Option Org Latex Toc Command
     |  |  |--- Option Org Latex With Hyperref
     |  |  |--- Option Org Latex Format Headline Function
     |  |  |--- Option Org Latex Footnote Separator
     |  |  |--- Option Org Latex Active Timestamp Format
     |  |  |--- Option Org Latex Inactive Timestamp Format
     |  |  |--- Option Org Latex Diary Timestamp Format
     |  |  |--- Option Org Latex Image Default Option
     |  |  |--- Option Org Latex Image Default Width
     |  |  |--- Option Org Latex Image Default Height
     |  |  |--- Option Org Latex Default Figure Position
     |  |  |--- Option Org Latex Inline Image Rules
     |  |  |--- Option Org Latex Link With Unknown Path Format
     |  |  |--- Option Org Latex Default Table Environment
     |  |  |--- Option Org Latex Default Table Mode
     |  |  |--- Option Org Latex Tables Centered
     |  |  |--- Option Org Latex Tables Booktabs
     |  |  |--- Option Org Latex Table Caption Above
     |  |  |--- Option Org Latex Table Scientific Notation
     |  |  |--- Option Org Latex Text Markup Alist
     |  |  |--- Option Org Latex Format Drawer Function
     |  |  |--- Option Org Latex Format Inlinetask Function
     |  |  |--- Option Org Latex Listings
     |  |  |--- Option Org Latex Listings Langs
     |  |  |--- Option Org Latex Listings Options
     |  |  |--- Option Org Latex Minted Langs
     |  |  |--- Option Org Latex Minted Options
     |  |  |--- Option Org Latex Logfiles Extensions
     |  |  |--- Option Org Latex Remove Logfiles
     |  |  `--- Option Org Latex Known Errors
     | [+]-- Group Org Export LaTeX
     | [+]-- Group Org Export ASCII

My questions are:
Do you get the same behaviour?
I have not been able to deduce the reason for this behaviour, ?
If I want to add a class should I do this in the (Option Org Export 
Latex Classes) or in (Option Org Latex Classes) or in both?

/rasmus