After going through the comments on the list here is where I think we are with 
changes to the document:

1) Section 3 

OLD
   It is important
   for the protocol carrying EAP to prove possession of the EAP MSK
   between the EAP Peer and EAP Authenticator.

NEW
The protocol carrying EAP MUST prove possession of the EAP MSK
   between the EAP Peer and EAP Authenticator.

ADD

In the context of EAP for Application-Layer Access the application is providing 
the EAP Lower Layer.   Applications protocols vary so their specific behavior 
and transport characteristics needs to be considered when determining their 
retransmission and re-authentication behavior as discussed in section 3.  


3)  Retransmissions

ADD 

2.1 Retransmission

In EAP, the authenticator is responsible for retransmission. By default
EAP assumes that the lower layer (the application in this context) is
unreliable. The authenticator can send a packet whenever its
retransmission timer triggers. In this mode, applications need to be able to 
receive and process 
EAP messages at any time during the authentication conversation.

Alternatively, EAP permits a lower layer to set the retransmission timer
to infinite. When this happens, the lower layer becomes responsible for
reliable delivery of EAP messages. Applications that use a lock-step or
client-driven authentication protocol might benefit from this approach.

In addition to retransmission behavior applications need to deal with
discarded EAP messages. For example, whenever some EAP methods receive  
erroneous
input, these methods discard the input rather than generating an error
response. If the erroneous input was generated by an attacker,
legitimate input can sometimes be received after the erroneous
input. Applications MUST handle discarded EAP messages,
although the specific way in which discarded messages will be handled
depend on the characteristics of the application. Options include
failing the authentication at the application level, requesting an EAP 
retransmit and waiting for additional EAP input.   

Specifications of how EAP is used for application authentication SHOULD
document how retransmission and message discards are handled.

4) Re-Authentication

ADD

2.2 Re-Authentication

EAP lower layers MAY provide a mechanism for re-authentication to happen
within an existing session [RFC 3748]. Diameter standardizes a mechanism
for a AAA server to request re-authentication [RFC
4005]. Re-authentication permits security associations to be updated
without establishing a new session. For network access, this can be
important because interrupting network access can disrupt connections
and media.

Some applications might not need re-authentication support. For example
if sessions are relatively short-lived or if sessions can be replaced
without significant disruption, re-authentication might not provide
value. Protocols like HypertextTransport Protocol (HTTP) and Simple
Mail Transport Protocol (SMTP) are examples of protocols where
establishing a new connection to update security associations is likely
to be sufficient.

Re-authentication is likely to be valuable if sessions or connections
are long-lived or if there is a significant cost to disrupting them.

Another factor may make re-authentication important. Some protocols only
permit one part in a protocol (for example the client) to establish a
new connection. If another party in the protocol needs the security
association refreshed then re-authentication can provide a mechanism to
do so.

Lower layers SHOULD describe whether re-authentication is provided and
which parties can initiate it.
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