Solid65 Stress relaxation

[ZoranB]

I found here a thread relating to Solid65 element after-crack behaviour:

http://www.eng-tips.com/viewthread.cfm?qid=249974

However, the thread is closed, so I started this one.

ansysfreak mentioned undocumented option:
When you want to use stress relaxation there is a undoc. keyopt(7)=2 (it works)

Do you have any explanation for this option? What does it exactly do?

Thanks in advance,
Zoran