My idea of this feature would be that hudson provide a mode where, instead of
just updating the workspace to the tip (latest repository revision) it would try
to catch up by updating to the next revision and run the target until it reaches
the tip.

Right now I do this manually from an ant wrapper script but integrating it in
hudson allows for fine grained identification of regressions. This is especially
important when a project get at a stage where performance improvements are the
focus.

for example, on our project, we do continuous performance testing so that the
impact of every commit is assessed by SLAMD jobs.

the principle is pretty simple but I don't know how difficult it would be to
implement.
Here's how I do it manually.
1. get workspace revision
2. get repository revision
3. if workspace revision < repository revision then trigger build

put that in a loop and you're set.