On 3/15/99  Dan Ingalls wrote:

>
[Other more subtle history management functions should be possible, but they are
of less importance.  One of these is assertion of post-facto structure as when 
you make a few changes to fix a bug in the system, but you now want to make it 
as though you had started a sepearate project for this when you did it, thus 
extricating those changes from the real thread you were working on.  Another is 
to see the full tree of history, so that if you undo 8 levels and go 6 levels 
deep in another exploration, you can pop out of there and jump to the 5th event 
in the original 8 and proceed from there.  This is all simple (except for the 
UI), as long as every event is added to a new path, rather than overwriting any 
old events.  Note that our current changes file has this property (beacause it 
is append-only), but there is no UI (let alone retraction mechanisms) for 
travelling to other than the point of the most recent save.]
>

I would love to be able to see the full tree of history and accomplish what you 
have described. Actually, I would like to be able to use such a capability to 
perform diffs and merges of arbitrary nodes of multiple branches and proceed 
with an independent branch (I'm not sure what to call it). Basically, I would 
like to pick up a bug fix from one branch, a feature from another, and proceed 
along a separate thread of changes. I have often had to do this kind of thing 
manually more than once and it tends to be a pain.
     
     Jerome