For years its been common for Christian to try to drop the jargon they use in evangelism and preaching. This is done for good reasons - to not create unnecessary barriers or confusion.
However in the context of council estates, it can also be.
1) Patronizing
2) Ineffective
1) Patronizing:
I say this because I believe that everyone is well used to jargon. Both Pop music and computer games contain a lot of jargon. Then there's jobs - every job has its own jargon. I would argue that people are well used to picking up jargon. Furthermore, it is the way we learn, by hearing something, and guessing what it means, and then having our understanding clarified or corrected by the context and further information. But this first point is really a minor point.
2) Ineffective:
More important than the above point, is that I believe it is ineffective, and this is for 2 reasons:
a) Culture trumps jargon:
You can avoid all of the standard Christian jargon, but if you are not sensitive to the culture, your words will easily fall on deaf ears. If your sermon applications are always about your stocks and shares - then you will have difficulty communicating to the unemployed. If your evangelism is about how God got you through your second degree, then you will have difficulty bringing hope to the single mum.
One the other hand, if you understand the culture you are trying to reach, then you can use jargon, but still reach the people - because you show how God speaks to their situation - and this trumps jargon.
b) Jargon is biblical and effective
The NT contains its fair share of jargon. And this jargon is an effective way of communicating truth. The first time, I tell someone about propitiation - I explain what it means (which takes a few seconds), then I am free to use it in conversation as much as I want. Now, they can be reading the NT at home and know what "propitiation" means when they see it, and now when I witness to them, I can say, "Yeah, remember Christ's death was a propitiation, and so .....".
Unfortunately, during the last few years when we have sought to drop jargon, we have also lost understanding of the words we thought were in the way. For example, many Christians today do not know what "justification" means, or "propitiation".
It seems to me then, that it is more effective to use the jargon the Holy Spirit gave us, and to explain it to people, rather than avoid using it.
Of course not all jargon that we use comes directly from NT words (for example "Salvation history"), but many of the above points still apply.