My understanding of the 'Keep together' is that I have to look only at what it is referencing and only that, not what I "think or want it to reference".
I also pay close attention to how 'keep together' is set to all of the objects inside another object (like a memo/string field in a detail section)
All of the Keep together options in the Section Expert are referencing only that particular 'band' or 'row'. I believe it also only references the preset height of that band as it is set in the design. It does not account for fields that 'can grow'. So it only 'Keeps Together' for a predefined height.
It sometimes appears to account for growing but it is more about how you set the 'keep together' option on the "growing" field that resides in the section and it is handling that requirement/setting.
An example of this is setting a detail the height of one single line of text and having it set to 'Keep Together' in the section expert.
Place a memo/string field in it with Can Grow as true and have it so it expands the field to a height more than the one print row.
If you set this to memo field as 'keep together' you will see new pages start to keep from breaking up the memo field. This seems like it is keeping the detail section together but I think it is only keping the memo field togther.
If you set the memo field to not keep together (uncheck the box) you will see that the detail section is not kept together because the memo field will straddle pages.
If you were to expand the height of the detail section (in the report design) to be more along the lines of 5 text rows and none of your memo field ever expand past 4 rows, the 'keep togther on the detail section will 'seem to work' because it is keeping it together based on the height of the actual detail in the design not the expanding memo field.
This is just my testing and what I could garner from it, definately not decisive.
Edited by DBlank - 30 Oct 2013 at 7:10am