Based on 6.1 PRD: https://issues.jboss.org/browse/BPMSPL-72. Affects several guides and both products BRMS and BPM Suite.
Since we already have the steps for installing in the domain mode for both BRMS  and BPMS , and as Thomas confirmed that there are no additional changes to the installer, from a documentation perspective, nothing needs to be done for this issue for 6.1. Could QE confirm?
Rajesh, the section of the documentation you have linked is only relevant to installing BPMS using EAP deployable package while BPMSPL-72 was purely targeted on the installer. However, I think no documentation changes are necessary. From QE's perspective, the only change in 6.1 is that we test if the domain mode configuration files (like domain.xml or host.xml) contain the same configuration properties as standalone*.xml files. From the user's perspective nothing has really changed. Only some inconsistencies between the configuration files has been fixed.
As I have mentioned in comment 2, no additional changes to the documentation were necessary so I am changing the status to VERIFIED.