I am not totally understanding which behaviour you would like to see.
But for GDS it is important to understand that by default there are two monitoring methods:
1) via PMF
2) via the specified Probe_command
Now if you unmonitor (-M) a gds resource, this will not disable PMF. So depending on your setup for the Failover_mode property, by default PMF will still issue a restart if it looses all registered pids for the corresponding pmf tag.
See http://blogs.sun.com/TF/entry/disabling_pmf_action_script_with for a short explanation if you also want to always disable PMF restarts for the GDS resource.
It might be sufficiant to change the Failover_mode value to LOG_ONLY in combination with the unmonitor (-M) for the resource to also prevent the PMF restart - but you would need to verify that. And it depends on your Sun Cluster version, since the LOG_ONLY value got introduced with SC 3.1U3 (and newer) if I remember correctly.
Greets
Thorsten