I mean when you are adding a new domain, CF can clearly tell if a domain already has dnssec on or not. Seems like something that should raise a warning to the user.
That would have been very helpful. The [Enable DNSSEC] button in the control panel is very assertive and confident through its casual and innocuous appearance.
Source: me, having lost access to my domain for 4 days for reasons that are not yet fully clear to me.