I think that the official line is that multiple sessions of Mstn is not supported, although this is possible (both with and without ProjectWise).

I think that it is increasingly unavoidable in a production environment. Reasons include:

1. Increasingly large files and processing times, including model switching lag

2. Need to work on multiple 3d models and 2d drawing views simultaneously when producing deliverables in a federated model environment.

3. Increased reliance on concurrent use of multiple OpenX apps to get work done.

4. ?

Increasing problems with upf corruption and 'wait chain' freezes are big productivity blockers, fee eaters.