Hi Steve,
This doesn't currently exist in the public release versions, nor is it currently planned for the next upcoming release.
That said, theoretically yes I think this could be implemented. I think you would want to think carefully about the underlying logic (for example, should the option only be available in the UI if the worker has already failed, to avoid someone accidentally interrupting a long-running job that was still in progress? What if there are multiple workers deployed but only one has failed? etc) and add enough abstraction to account for the different ways Gearman can be installed and configured, but at first glance I see no reason why it couldn't be designed and implemented in the future. Keep in mind however that I'm an archivist, not a developer or system administrator, so there may be additional factors I haven't considered.
I don't personally know of any community users who've reported doing so, but if someone has, hopefully they will see your post and respond.
Cheers,