[TYPO3-templavoila] templates and subtemplates question

[Bartosz Aninowski]

Hi
I don't know if I dont understand or I've missed somthing but I am not sure 
how subtemplates works.
What I want to achieve is simple map  menu and content in main templates and 
then inside "content" to choose different subtemplates of content fg with 
one column two or other layout.
Some kind of MTB bevaviour.
Looking into doc I found that I can create varoious kind of FCE and use it 
inside my "content" but I cant inherit this layout so I need to add FCE to 
all my subpages.
So the only solution is to add new template with the same DS and then add 
new fileds [fg filed_firstcolumn, field_secondcolumnl] and leave not mapped 
others not used in this templates, right?
I hope I am clear enough.