Galling is not locaized to a single metal combination. Thread galling seems to be the most prevalent with fasteners made of stainless steel, aluminum, titanium, and other alloys which self-generate an oxide surface film for corrosion protection. During fastener tightening, as pressure builds between the contacting and sliding thread surfaces, protective oxides are broken, possibly wiped off, and interface metal high points shear or lock together. This cumulative clogging-shearing-locking action causes increasing adhesion. In the extreme, galling leads to seizing - the actual freezing together of the threads. If tightening is continued, the fastener can be twisted off or its threads ripped out.
I have been an aerospace engineer for over 15yrs and I have seen this happen many times, it is more apparent in single metal combinations but by no means localised to this, as I have seen it in disimilar metal combinations as well.
I do agree that a good driver is essential, however a good driver very rarely makes up for a poorly formed fastner.
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