Name Selection in Columns from the Rows/Row Selection menu is great to define labels by selecting different subsets and writing the corresponding labels step by step into the same "label" column:
https://community.jmp.com/t5/Discussions/manual-grouping-extended-version/td-p/540203
The current behaviour of the function is:
a) just do something if the user entered a value [This feature enables the user to "collect" information by writing values again and again to the same column - without over-writing existing labels in other rows]
b) If there is already a label in a selected row, it is replace by the new label.
This is the reason why the function can just be used for disjunct label groups and cannot be used for "multiple response" entries.
A second response would just replace a first one.
My wish: an option to append the entered string, if a selected row already contains an value:

This will allow to collect "multiple response" entries like in the example below.
Would be great if the function automatically handles the commas right (i.e. no comma for the first label).
Additional useful options:
- prepend text
- search and delete text
- search and replace text with another text
...
dt = Open( "$SAMPLE_DATA/Big Class.jmp" );
dt << New Column("activity", Character, "Multiple Response");
dt << Clear Select << Select Rows( [2, 4, 8, 9, 20, 25, 26, 35, 36] );
wait(2);
dt << Name Selection in Column( Column Name( "activity" ), Selected( " ,football" ) );
wait(2);
dt << Clear Select << Select Rows( [2, 4, 8, 12, 22, 27, 28, 29, 30] );
wait(1);
dt <<NAME selection="" in="" column=""></NAME>