[TxMt] Why relative paths and not absolute in project files?

[BarryW]

I just went through a cleanup and organization of my Desktop as it was
getting a bit messy.  Part of that mess was the number of TM Project
files that started to collect there.  I decided to put them in a
folder and then drag the folder to the Dock so I could get a popup of
the contents, the same as the Documents and Downloads folder.

After I did this I found that that Textmate would open, but the
contents where in red coloring and not available to me.  After some
looking I found that files contained the path to my files relative to
where the Projects file was created.  I thought that at this point it
would be faster to simply edit the files in Terminal with vi rather
than re-create everything, and also better since I would retain all
the settings that were embedded.

As a test on one of them I changed the path from a relative path (../
Sites/foldername) to an absolute one (/Users/myname/Sites/foldername)
and it opened everything the way I expected.  But after I closed the
project in Textmate, I found that the path had once again reverted to
relative again (../../Sites/foldername).  I ended up changing a dozen
or more files anyway, and now all is good, but I can't imagine what
the effort would have been if I had many, many projects.

So I guess I am wondering why this is the behavior, and why Textmate
can't use an absolute path which would make management of the Project
files a lot easier.  And before someone asks, I do a lot of online
testing of different installations and I like having direct access to
the Projects without having to navigate to them in the Finder and
finding them in the actual folder name. I also don't have the Project
file(s) cluttering up my site files either.