I live near Dewsbury, and I don't really think it is accurate to position the situation in Dewsbury as a "Muslim" issue at all.
I think the "Muslim" label in these circumstances confuses and obsfucates, and it is noticeable how no-one ever refers to Arab, Turkish, Kurdish, North African or Central Asian communities in Britain as "Muslim" in the same way.
I would suggest that the problem in Dewsbury is two-fold: you have a immigrant community that originally came from a very undeveloped part of the Indian sub-continent and has continuously practiced chain migration, and you have a religious sect that functions very much like a puritanical cult.
A point to note is that Tablighi Jamaat is a product of the Indian subcontinent, and its adherents are overwhelmingly of that background. This may go some way to explain why some members of the Savile Town community in Dewsbury appear to harbour animosity towards people from an Arab or Kurdish Muslim background -- apparently, they are perceived as "the wrong kind" of Sunni muslims.
Indeed, there was a rather shocking case a few years ago of GBH against a young Iraqi asylum seeker by members of the Savile Town community, and the young man was left with severe brain damage.
In light of this, I think it is very interesting that you are getting young men from this area joining ISIS, which is basically engaged in a campaign of slaughter against Arabs, Kurds and other minorities in the Middle East.
Put it this way, the cynical part of me strongly suspects no-one from Dewsbury would join ISIS if their theatre of war were in Pakistan. 