What is the increase in x factor when you barlow a binoviewer

[Saturninus]

I understand that if you increase the distance between the barlow and the eyepiece, the multiplication factor increase. So if I move a 2x barlow in front of the diagonal instead of the eyepiece holder, the magnification goes to 3x or so. 

What happens if I attach a 2x barlow element to the front of a binoviewer? Does it also go up to about 3x?

I was thinking about getting that Baader Zoom barlow, which has a magnification factor of 2.25. It comes with a T-adapter, so I could theoretically thread it to the front of a maxbright binoviewer, but if that results in a 3x magnification factor or more, it will result in powers too high to be useful...

Anyone ever try this?