TVS-diodes: To be or not to be

Hello,

I have a question regarding coils for proportional valves controlled by uni- or bidirectional COUT outputs:

As of now, we are using the coil "Sun Hydraulics 770-924" for some of our proportional valves. That coil includes a TVS-diode:

That contradicts the (somewhat loose?) statement in the MC4x Instruction book:

I understand that there is some kind of diode solution internally in the MC4x for COUT's. Does that solution make the coil's diode solution redundant?

Some information regarding the coil:

The coil _appears_ to work just fine in our application but I haven't checked it with an oscilloscope during operation to see what is actually going on. Maybe the TVS-diode in the coil is never active? 

In short:
Is it OK to use this coil or does it, in some way, interfere with functionality? Or should I interpret the Instruction Book strictly and use a coil with no diodes at all?

I thought that with your knowledge of the MC43's internal hardware perhaps you could shine some light on the matter?

Much appreciated,
Christopher Fridstaden