In order to improve fluidity, rearranging index card contents is frequent. Rather than having to cut and paste, I wish it were possible to use drag and drop in the Corkboard.
You can use Drag and Drop in the Corkboard, but it does not work obviously when you have manually selected some cards. Selecting a container Binder item will allow you to rearrange the sub-items in the Corkboard view.
Why ’ obviously’ ? The purpose of the post is to suggest it should work.
What does this mean?
I drag and drop on the clipboard all the time. Not sure what you are having trouble with. By rearranging in a subgroup I assume he means that if a sub-folder has say, 8 sub-items, Viewing that subfolder in corkboard view enables you to drag the sub-items around.
Are you saying that if you have 4 items in a cork board, you can’t move item one to position 3 just by dragging it there?
I mean dragging text from an index card and dropping it onto another index card. It doesn’t work for me. Does it work for you?
I misunderstood your OP to mean dragging and dropping (rearranging) the index cards themselves. Index cards can themselves be containers, whose contents can be index cards (sub-items), so your use of “contents” in your OP was a bit ambiguous. 
Thank you for clarifying you meant text.
Dragging text from one spot on an index card to another spot on the same card works. Dragging text from an index card to another index card does not.
Dragging a card over another card is treated like moving the card as a sub-child and not like moving its contents to the new card. If drag-and-drop moves the card contents, it might easily overwrite one card contents with another card contents by mistake, which cannot be reverted. This might lead to unexpected data loss, which should never happen.
I didn’t mean moving the card, nor the whole card content. I meant moving a segment of a what’s on a card to another.
Say on Card 1 you have written:
This
That
On Card 2 you have:
Event
I’d like to drag ‘This’ from Card 1 and drop it onto Card 2 after ‘Event’, so Card1 would be now:
This
and Card 2:
Event
That
That’s the kind of operation I do all the time when rearranging card contents. Having to cut and paste is a drag (no pun intended).