Data Level Security implementation question

Question

I had a quick data-level security scenario and wanted to solicit any input from the experts.
In our current Subject Area we have one Presentation Layer using one Business Model. In this Subject Area have a Task and Employee Dimension. There is row-level Security on the Task Dimension that is done in the Business Model on the LTS Content tab. There are a batch of reports built off this Subject Area.
There is now a request to build a new batch of reports, however, they want to now filter on the Employee Table and NOT filter on the Tasks. So the opposite of what has been applied above.
From my perspective there are only a few ways this Security can be applied
Business Layer: Basically either create an Alias of Employee and Task or build a second LTS for both. Then create new columns and map to these accordingly. Basically have 2 of each column in the Business Layer. One with Security applied and one without.
Presentation Layer: Created a second Presentation Subject Area and apply the security at the Presentation Layer and remove it from the Business Layer.
I know a third option could be put security on the Role/Group but for this case these reports are open to everyone.
I'd just like to verify from the experts that I may have covered all solutions for this scenario or if there are any other suggestions?
Thanks!

Answer 1

Alright...
If you have two LTS say A & B (basically duplicate) then add a column say LTS Indicator and assign 'A' for LTS A and 'B' for LTS B. Add the fragmentation content and apply the security filter and you can also create two different Presentation folders under same Subject Area if users have Answers Access so that the users know if they are querying for LTS A or LTS B.
Similarly, build your reports making use of LTS indicators which will BI server to pick correct LTS. Say, where you want LTS A to be picked...use filter of LTS Indicator = 'A' and thats it.