[Bug-ddrescue] Accidentally ran ddrescue on an r/w mounted partition

[jt512]

I am almost done running ddrescue on a 1.5 TB partition (just 0.2 more
TB to go), and just discovered that the partition was mounted
read-write.  When I started ddrescue I thought that the partition was
unmounted, and so I think that it got mounted somehow part-way through
the rescue, but I have no idea how far along into the rescue that
occurred.  The online manual says not to try to rescue an r/w mounted,
as the copy could be useless.  So, my question is, what do I do now?  Is
the copy almost surely bad?  If not, is there a practical way to check
if it is ok.  For instance, if I can read a handful of files, can
I conclude that the copy is good?  Or, should I just chuck it and start
over?

Thanks in advance for your advice.

Jay