What is the purpose of heavy cream in a mushroom duxelle? I'm planning on preparing a beef wellington for the holidays and am following a recipe whose duxelle recipe is defined:


  
  In a food processor, pulse the mushrooms until finely chopped. Then, finely chop thyme.
  Over medium heat, melt butter in skillet. Add mushrooms and combine with butter. Add thyme. Using a garlic crusher, crush garlic and add
  to mushroom mixture. Continue to combine over medium heat for about
  10-15 minutes or until the mushrooms are caramelized.
  Once the mushrooms are caramelized, add a generous splash of Cognac and stir to deglaze the pan. Add heavy cream and cook for several
  minutes or until all the moisture is gone. You should be left with a
  paté-like mixture.
  


Most of the ingredients make sense to me in their contribution to flavor and/or texture but I can't seem to figure out why heavy cream would be added to the duxelle. I thought the mushroom pâté would be thick enough alone, so I can't imagine the heavy cream contributing to the duxelle in that respect.
The heavy cream is basically protein and fat, with some water which you're cooking off.

I think the cream is there to bind, as the mushrooms will probably not quite "stick" well enough.

It also adds to the volume of the completed paté.

Last, but not least, I have been told that cream is tasty. It's there, among other things, to add to the flavour.