Here is an interesting article written for financial advisors that talks about the disconnect between estate planning for a client and the heirs of that client.  
FFP Wealth Management has been way ahead of the curve on this issue.  The estate plan is only half of the equation when you are talking about tax liability because inherited retirement plans retain the income tax liability after the owners death.   One person could have 4 heirs with 4 completely different income tax situations.  The heir ABSOLUTELY needs to understand their income tax situation before they inherit any monies so that the best tax strategy can be implemented.  
That means an estate plan should include a meeting with the potential heirs and getting to know their situation BEFORE the time comes when that inheritance is realized.  It also means heirs should sit with a qualified fiduciary to help them determine the best strategy prior to accepting an inheritance.  

Heirs article here