I have a working circuit that delays the off time of a relay.

It simply has a 10uF in parallel with 3.3M ohm that is tied between the
Gate and Source of a BS170.  The cap keeps the Gate voltage high and slowly
discharges.

In the original design I had a protection diode across the relay coil.

But I need to make changes and space is limited and was thinking the diode
can go.

The rationale is that the coil never suddenly turns off so no inductive
spike.  The current gradually decays as the cap discharges over a 1.5 min
period.

The data sheet also shows a body diode for the BS170.

So what say ye, is there any argument for keeping the diode in this case.

Cheers Justin
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