However one measures rheology parameters, ("Measuring Concrete Rheology" May 2003, p. 22.) keep in mind that it is all relative. If a certain set of parameters gives you a specific strength, specific durability, and acceptable appearance related to those parameters, then that should be all that you are looking for.
I don't understand why anybody wants to make this so complicated when it comes to SCC. As long as you can correlate certain properties to a set of rheologic parameters, you should be good to go. One may need to get more specific where there is heavy congestion of steel and other special circumstances.