I think we can probably leave the stuff on party organisation/culture to one side for now; in that we are both, broadly speaking, revolutionaries within the Leninist tradition who favour a far more "libertarian" culture than "Leninist" groups have usually possessed, I think that we agree. However, the point about your claim not to know whether you're in a minority or not being "risible" can't be explained away by pointing out that you haven't voted on the issue - you don't have to have had a formal vote on every question to judge what the perspective of the majority of an organisation is, and personally I think it's clear that at least superficially, what you've said here goes against the grain somewhat. Again - this isn't a criticism (far from it), and I hope you're able to fully debate through these issues within PR.
On the substantive question of the united front, I'd say that the idea of a "united front" with non-working class forces fundamentally misunderstands the tactic. It is about breaking elements of the workers' movement away from reformist misleadership; in what sense does this apply to the Mahdi Army? Of course we want to break working-class individuals away from such organisations but trying to apply the united front tactic to such a scenario is square-peg-for-round-hole stuff. Breaking Iraqi workers from the Mahdi Army implies organising against Al-Sadr (not just independently of him) as a bourgeois element, rather than simply trying to "expose" him as somehow insufficiently anti-imperialist.
I don't rule out the possibility that in a situation of armed working-class resistance to, say, an occupation it might be necessary to attempt to reach military/tactical ententes with a force like the Mahdi Army. But I think that a) the likelihood of the Mahdi Army agreeing to that is so incredibly remote as to make talking about it somewhat sophistic and b) to make it the point-of-departure for what we as British revolutionaries say about Iraqi workers' resistance to occupation is a grave error of judgement. In the first instance we should be talking about how Iraqi workers can defend themselves against organisation like the Mahdi Army, not about how they can ally with them.
The history of class struggle across the Middle East and beyond (the Iranian counter-revolution is the obvious example but there are plenty more) shows us very clearly the role that Islamist forces ultimately play in relation to our class. Our job in that context isn't to play up the possibilities of what are ultimately incredibly incidental potential military alliances ("ceasefires" is probably a much better word) but rather to explain very clearly and loudly what the Islamist forces represent in class terms.
When the hegemonic elements on the left in the UK have collapsed so completely into tailing these forces in the most obscene, treacherous way I think the responsibility to explain those things becomes all the more acute. The AWL bends the stick too far sometimes? Maybe, but when the loudest voices (i.e. the SWP) are coming out with such utter shite it's difficult not to sound shrill.
In summary, I think your position on the AIUF both a) drastically misunderstands the class nature and application of the united front tactic and b) abdicates, or at best subordinates, our very real and urgent duty to tell the truth about the nature of Islamism and its relationship to working-class politics and the socialist project.