Thread Subject: outerPosition changes when xlabel is moved

The outerPosition property usually includes the xlabel, ylabel, and (as far as I can tell) all children of an axis. But after moving the xlabel, the outerPosition now ignores it, and the lower limit corresponds to the xticklabel.

plot(1:10)
xlabel('xlabel')
set(gca,'position',[0.3 0.3 0.3 0.3])
xlp=get(get(gca,'xlabel'),'position');
oP1=get(gca,'outerPosition')
set(get(gca,'xlabel'),'position',xlp)
oP2=get(gca,'outerPosition')
set(get(gca,'xlabel'),'position',xlp*0.9999)
oP3=get(gca,'outerPosition')

of the axes properties, only outerPosition and extent have changed. The properties of the xlabel itself are identical to before. Is this a bug?

I want to align the xlabels on several axes, and use the outerPosition property to check that they haven't drifted out of the figure, or overlap the xticklabels. If I can't rely on the outerPosition property, does anybody know how to do this?