conditional

[navit]

1) With the resources they had, it was possible for them to finish the work. But they didn't.
2) With the resources they had, it would have been possible for them to finish the work. But they didn't.

Is the 'but they didn't' redundant in '2'?

Is '2' equivalent to

3) With the resources they had, it would have been possible for them to finish the work had they wanted to do so.

Gratefully,
Navi

[Alan]

Is the 'but they didn't' redundant in '2'?

Essentially yes, but, for clarity, there is no problem in adding it.