After going through the discussion thread, these are my views:
We are talking about 2 different things. One is User Behavior and the other is Different types of Test.
In my opinion, the User Behavior will remain the same across Benchmark Test, Scalability Test and Soak / Endurance /Longevity test. It would depend on the User Behavior.
For eg: 1. For an internet banking website, a user would normally login to the system, do his transactions (like checking account balance, Fund Transfer etc..) and logout.
2. For a Data entry operator or Backend operator, the User would log into the system in morning and do data entry (like create / submit proposals, Submit transactions etc...) and will continue doing that throughout the day and will logout of the system at the eod.
The User behavior should remain same for Load Test and Soak Test. Only for some specific targeted tests like sync tests we would be altering the User Behavior, wherein we expect a very high concurrency on a specific screen. A good example would be Flash Sale screens for Mobiles on e-retailer sites.