Never used Microphen but it is said to increase film speed by maybe half a stop so you have a film at, say EI 600 which needs pushing by about 2.5 stops to 3200. Sounds do-able with the usual drawbacks for pushing.

I'd be interested in how HP5+ pushed to 3200 compares to D3200 at EI 3200 and you are in the ideal position to let us know, having shot both at same event and in same lighting conditions

It might help some here to decide if HP5+ pushed to 3200 beats D3200 at 3200.

I for one would appreciate scans of each film for comparison and your conclusions. Thanks