Both subjects were at the very least eccentric. Despite the dandyish, sexually ambiguous nature of Disraeli, it's Gladstone who emerges as the strangest character. Although the 'night walks' and psychosomatic illnesses are well known, just how screwed up he was - sexually, emotionally, temperamentally - is extraordinary. He seems pretty much out of control a good part of the time. But given his remarkable political success he nevertheless obviously functioned at a very high level. (By the way, it's Disraeli's unaffected and deeply felt love for his wife that makes one see him as fundamentally a sympathetic 'uman been').
Makes one wonder what biographers will make of our current crop. Brown for instance always strikes me as a monster of egotism and a mass of writhing something or other. Can't wait to discover the backstory.
Pondering why Gladstone's strangeness did seem so striking to me, despite my having read other biographies (Roy Jenkins's is the most readable), made me appreciate the effectiveness of Aldous's approach. He really manages to illuminate the two key things I think one wants to know when reading biographies (at least of 'great men'): what it would have been like to meet them (get a sense of their presence) and how their personality meshed with events to make a difference.
Most biographies don't relate events in a way that gives one the ability to imagine being in the presence of the subject; it's more akin to straight history writing. They also don't stray into the subject's interior life and try to reconstruct 'mentalite'. Without this it's difficult to see how personality influenced those around the protagonist on the 'micro' level to result in large - history-making - changes at the 'macro' level. Aldous does this by 'novelising' somewhat, relying inevitably on some speculation and inferences.
This approach is often dismissed as a bit lightweight but I think in the right hands it's the most effective way to illuminate a life and its impact on events. To do it well requires novelistic skills but these do need to be governed carefully. If one is not to stray into unwarranted speculation - even err into outright fiction - the work needs to be underpinned with pretty exhaustive research and a very careful extrapolation of the materials.
The greatest exponent of the 'novelistic' approach is Robert A Caro. He succeeds to such an extent that I would argue his biographies of Lyndon Johnson and Robert Moses are some of the greatest works of literature of our era in any genre. I really can't put bounds on the splendour of his achievement (wow).
But examples of how it can fall flat on its face are out there too: Edmund Morris's Reagan biography 'Dutch'. He just went too far in making things up - to the extent of inserting himself into the narrative as what I guess you could describe (confusingly) as a fictional character. Postmodern I suppose.