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I have been using drift alignment with PHD2 though I have just bought a Polemaster from another IS user as without ready access to a good compass it is easy to find yourself degrees off the mark and then you chase yourself all over the sky drift aligning. I put in alignment notes in PHD2 to say which way to move the mount to correct which misalignment (E.G. "Raise axis to lower trend line when pointing east" and similar) but when you start a few degrees away it is easy to doubt yourself when adjustments don't seem to be working when the problem is that you are just a way off and cant readily see the trend line difference as it looks like a ski jump.
I am expecting once I am familiar with with the Polemaster to align closely to the pole fairly quickly with that and then drift align for a final check.
I would say a couple of things if you drift align, point up near the meridian and do the mount azimuth axis first and always point to the same side of the meridian as east or west will reverse the direction of drift for the same error in mount azimuth, same goes for the altitude.
It is easy to isolate the error in azimuth by pointing close to the meridian, where when you do the altitude adjustment you will probably be pointing 15 or 20 degrees above the horizon which means that any drift you see is a result of both altitude and azimuth errors. If you had to point 45 degrees off the horizon to do your altitude adjustment the drift will be equally impacted by both alt and az errors.
When you are happy with the azimuth, lock the center bolt down properly, I was fiddling on the weekend and even a tenth of a turn back from being properly tight makes a huge difference to the altitude of the RA axis, you are trying to be down in low arc second errors and a tweak of the lock bolt is more like degrees. I realised that as I was playing around and looked through the polar scope while I did the bolt up, I had Octans nicely in the reticle and when I did the bolt up it moved vertically by half the size of the asterism itself!
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