For as long as I remember I have been able to resync objects by setting
the association state to 3 or 4.

For example if the state was 4 you could change it to 3 and if it was 3
you could change it to 4 to trigger a sync.

It looks like that no longer works with IDM 4.5.3, can somebody test and
confirm my findings?

I get this in the driver trace when setting the state to 3:

[02/04/16 15:35:19.775]:Generic Null ST:Start transaction.
[02/04/16 15:35:19.776]:Generic Null STiscarding transaction because
of disabled association or optimization.

Funny thing is that iManager with the latest plugins changes the state
to 3 if it is 4 when doing a migrate.
NetIQ Identity Manager 10.7.20160113 NetIQ Identity Manager Plug-ins for