With 2.1 the secret key import result changed.
I've asked about this on the mailing list before:
https://lists.gnupg.org/pipermail/gnupg-devel/2016-March/030877.html
I think this should be treated as a bug.
The result:
gpg: Total number processed: 2
gpg: imported: 1
gpg: secret keys read: 2
gpg: secret keys imported: 1
Is the result for "GnuPG imported all secret keys in that file" but but the
result shows that it read more then it imported.
This result indicates that not all keys in that file were imported, which is not
true.
If the intention is to include information about subkeys that should be an extra
number.