Attempting to connect to a ReplicaSet using a seedlist with multiple members will fail if any of the members is unavailable at the time the connection is attempted, even if the ReplicaSet overall is perfectly functional.

This seems to violate the spirit of the SDAM spec outlined here regarding I/O operations in the constructor. I realize this isn't a 'constructor' operation in the typical JS sense, but the ultimate effect of this implementation is essentially called out as undesirable behavior:

When the deployment is passing through a strange state, long-running clients may keep working, but any clients restarted during this period fail.