They came into conflict last year over whether or not it's reasonable to criticise Islam without having read the Koran. To summarise, Richard said "yes" (in a typically controversial way), but Qasim said "no".
Both are right. Let me try and explain why I think this.
The difficulty here is that a religion and the associated culture aren't a single thing; far from it. A religious culture can be divided into at least three things:
1. The holy books, or doctrines, or scriptures. These have usually been written some time ago and are generally considered to be the place to look to settle disputes about beliefs or commandments.
2. The culture. This consists of activities and traditions that have become associated with a religion, such as ceremonies, types of food, codes of dress and so on.
3. The believers.
None of these in isolation define a religion. A religion is a combination of what certain books say, what believers believe, and what believers do. These factors can come together in very complex ways.
For example, the doctrines of the Catholic Church are very clear - contraception is forbidden: This is in no doubt. Yet, in the USA, the overwhelming majority of Catholics are happy to use contraception. So, the question "What is the Catholic view of contraception?" doesn't have a simple answer, because it depends whose views you are talking about.
So, is it reasonable to criticise Islam without reading the Koran? That depends entirely on which Islam you are talking about. If it's Islam 1, the holy books, then it isn't reasonable, because you have no evidence on which to base any criticism. But, if it's Islam 3, the believers, then it can be reasonable, because the believers can be clear about what Islam means to them, and then you can criticise their Islam.
Religion type 3, the believers' religion, is what actually matters most, because that determines the impact of a religion in society. In some (but by no means all) Western societies Catholicism's approach to contraception is relatively harmless, as no-one takes much notice. In those societies Catholicism's approach to contraception isn't something that needs to be urgently addressed.
So, does it make sense to talk about a true version of a religion? I doubt it, because of this composite nature of religion. What it is like to be a member of a religion can vary considerably depending on where and when you are a member. This is why I have a problem with those who insist that moderate or liberal versions of religions 'aren't true' in some way, and uses that to dismiss moderates. It just doesn't make sense.
This seems to me to raise the question of how relevant it might be to take into account the contents of the books of a religion when discussing the social effects of that religion.
If my believer friends will forgive me for this, I'm going to use an analogy to try and help explain what I mean. There are rules of the road, which, in the UK, are combined in the "Highway Code". These explain what a driver is expected to know to be a good and safe driver. They are the "doctrines" of driving. Ask almost anyone who drives if they are a good and safe driver, and they will say "yes". Ask them if they believe in the doctrines of the road, and they follow those doctrines and they will say "yes", but if you watch people drive generally, you will get a different picture. Just consider the number of people who drive over legal speed limits in the UK - it's vast. It's likely that the traffic police take this into account, and only prosecute really fast drivers on motorways (not that I am recommending breaking the law!). And yet, few if any of those people who drive fast will consider themselves lawbreakers. To them, the speed limit might be "interpreted" as meaning "don't drive too fast".
Two people can say that they follow the law, and they believe in the law, and in their minds they are both right, and yet their behaviour might be very different. If you want to find out what it means to be a driver in the UK, you have to watch the behaviour of drivers. You won't get what it means to be a driver by reading the Highway Code, at least not by only doing that.
If you want to see what it means to be a believer, you have to watch the behaviour of believers. You won't get what it means to be a believer by reading only the holy books. Furthermore, you can't say who is a "true believer" based on those books any more than you can say who is a "true driver" by pointing at the Highway Code. It doesn't help to point at the words in a holy book and insist that all believers believe that any more than you could point at a speed limit and say that all drivers believe in that. All you can do is get evidence - observe.
Surely the point of criticising religion politically is to decrease suffering and oppression, and these are reduced when moderate versions of religions replace fundamentalist versions. This is why I welcome engagement and co-operation with moderate and humane versions of religions, such as Ahmadiyya Islam, because it's vastly better than fundamentalist Islam; and has distinctly positive aspects such as the active promotion of secularism and freedom of belief (including none).
However, I also agree, to an extent, with Richard Dawkins - it isn't vital to read the books of a religion to criticise the behaviour of believers. But I would add this: reasonable criticism should surely be based on all the evidence, at least all the evidence that is easily available, and both the Bible and Koran are easily available.