OK, I now see that is very slightly different - Size To Fit means both Auto Grow and Auto Shrink. What you're asking is for a way to grow without also shrinking as another way of autosizing a cluster.
Perhaps this idea shouldn't be closed, though it would help if you gave some more information as to why you think this functionality would be useful.
Also, is there a reason not to want the same functionality for controls and indicators?
The difference between 'Autogrow' and 'Size to Fit' is that Autogrow will not give space back. I may not want that particular option myself, but if that is specifically what the OP is after, I have to agree that it is not already implemented. Already rejected, perhaps, but not implemented.
Size to Fit came to my mind as well, I would suggest a few more details in the idea post if the distinction is so important.
