Maybe because while I had a background in science and technology by education and training but worked in sales/biz dev/ops strategy finance type stuff my perspective on issues such as this are informed in a way that might or might not appeal to you but in the interest of increasing understanding, here it goes:
I think there can always be arguments about data and its interpretation and more argumentation and interpretation does not necessarily bring most people closer to understanding on human affairs and belief systems type of issues.
<Also, please note that I am not trying to convince you, just considering different ways of looking at a situation >
So let's say that you are right and there are violent acts prescribed in some texts. I realize that I will get nowhere if I were to argue with someone on the accuracy or interpretation of those texts (* primarily I think this happens because people have different implicit belief systems )...even though this can be quite satisfying to try.
However I am more likely to create a change in the direction I want if I am able to demonstrate the benefits of my belief system without explicitly challenging the belief system of the other (hopefully they will reach the conclusion you initially wanted but do it on their own and that makes all the difference...it might be very tempting to say "look I told you so" but that would only be detrimental to the process).
From an execution standpoint to me it would look like building on the parts that are common to each party and even (genuinely) recognizing some of the good things in the other's doctrine. So basically instead of starting conversations with "I read that your texts say you should behead kafirs/non-believers" to me personally it makes more sense to be talking about the invention of algebra in the Arab world or how so many stars have arabic names etc...I think this puts the "adversary" in a more receptive state and appeals to their higher instincts which can then form the basis for productive change.
That is why I also think say theocratic Islamic regimes/groups that are "anti western" will always appeal to the lower instincts of their followers by calling out the moral decadence of the west and pointing out our women with short dresses and MTV type culture as a moral decadence of the west but will not talk about great inventions and progress made under their own ancestors/kings/cultures previously.
* Once upon a time, a shoe company sent two salesmen to Africa to determine the market potential for their products. One salesman was sent to the east coast of Africa, while the other salesman was sent to the west coast of Africa. Both the salesmen completed a basic survey of the target market and called back to the office. The salesman sent to the east coast of Africa reported “No one here wears any shoes, there is no market for us here!”. The other salesman sent a message “No one here wears any shoes, there is a huge market for us, send inventory fast!”.