DMVPN over IPsec

Hello laz,
I have a few questions.

  1. Would you please let me know the order of operations when a packet is being sent over a DMVPN protected with IPSEC tunnel?
    My understanding is route lookup which is the tunnel interface-----GRE encapsulation-----IPSEC encapsulation—exit out of the interface. Please let me know if it is correct?
  2. If the IPSEC tunnel goes down still I should be able to send out traffic through the GRE tunnel. The only problem is the traffic will not be encrypted. Is it correct?
  3. For the sake of this conversation, let’s just say I have only one SPOKE in a DMVPN setup and I do not want to run any routing protocol over them. The tunnel IP addresses are from two different subents. If I configure static route pointed to the tunnel interface, should both hub and spoke not be able to communicate back and forth? Needs clarification.

Thanks as usual.

Azm