I imagine that in extremely calm conditions, the alternate flap switches could be used to effect pitch change, though that might make for an interesting approach and landing. Travel on the normal flaps takes about 45 seconds. Go to the alternate switches, and the rate is greatly reduced; full travel takes five and a half minutes. That's a little long to be making corrections while flying an approach. Certainly if it's all you've got, it's all you've got...but you're going to get faster changes by trimming for a speed and using power.
Further, if you do indeed have a full hydraulic loss, and power is a big part what you're doing, then you also have no roll control beyond splitting the flaps...again, better hope for a calm day, an extremely long runway and very uniform engine response.