IOS - Lan-to-Lan with two dynamic peers. (Both can initiate)

Original credit goes to Zsolt Horvath from Cisco TAC.

Goal:
Establish L2L tunnel between two hosts with dynamic IP. In this case both are registered to a dynamic DNS service (dyndns, no-ip or others). 

Problem.
IOS does not do name resolution when it's IKE responder. Documented here:
http://tools.cisco.com/Support/BugToolKit/search/getBugDetails.do?method=fetchBugDetails&bugId=CSCsc92917

Usual resolution:
Use "dynamic" keyword on one peer side and dynamic crypto map on other.
Resulting in only one peer being able to initiate.

A solution when both peers are able to initiate:
This will require having both static and dynamic crypto maps, but with dynamic being first (to account for responding) and static crypto map later (to account for initiating).

Configuration in a nutshell:
R1:

crypto dynamic-map DynamicMAP 10
  set transform TRANSFORM

crypto map StaticMAP 100 ipsec-isakmp dynamic DynamicMAP

crypto map StaticMAP 110 ipsec-isakmp

 set peer R2.provider.tld dynamic
 set transform-set TRANSFORM

 match address 150 

R2: 

crypto dynamic-map DynamicMAP 10
  set transform TRANSFORM
crypto map StaticMAP 100 ipsec-isakmp dynamic DynamicMAP

crypto map StaticMAP 110 ipsec-isakmp

 set peer R1.provider.tld dynamic
 set transform-set TRANSFORM
match address 150

Please note:
Note1: You need to have DNS resolution enabled on routers.
Note2: Remote access IPsec VPN should also work.
Note3: While in theory, isakmp key and identity with hostname should work. This has only been tested with identity address and a wildcard isakmp key.