"Work arounds have a place but with processing speed as poor as this, work arounds dont leave much brain power left over for learning and doing."
I actually disagree with this sentiment...
If you think of methods we show children, in say, Mathematics, they are rarely the 'quickest' way of doing things.
For instance, if we want to know what the answer to "3 apples cost 2 pence each, and 1 banana costs 5 pence. How much would I need to spend?", we would quickly be able to work out in our head that the answer is 11.
However, we would teach the children to do this:
3x2=6
1x5=5
6+5=11.
We don't teach them those methods because they are 'quick'. We teach them because it lays a good foundation for trickier sums. If the method is right, then they can break down any task.
Processing issues really come out when the thing to be processed is more difficult.
I know that if I am trying to think about things that are just day to day routine things, I can hold many many thoughts in my mind at once. What am I doing for dinner? Will DD1 get in from school early or later, is DD3 going to be tired and grouchy?, etc.
But if I was trying to think of a complex subject like the country's finances, and the banking crisis, and the benefits reforms, I might find it harder to think about 3 things at once.
I think the very KEY to Processing difficulties lies in taking away the processing. Make the processing easier, by reducing the amount that needs to BE processed.
Very visual techniques, used in TEACHH (I know loads of posters here hate it, but I was talking to my DD1's Outreach teacher yesterday, and I saw the real value of TEACHH as it is meant to be done - inspirational). Take away the mystery, the massive processing.
So, first, perhaps, focus on breaking down tasks into discrete sections. Make sure that your DS isn't having to try and remember what might be next after the current task. Think of it as this: He has 4 'bars' of processing. If he is worrying about the next task, he might only have 2 'bars' reserved for the current task. So make sure that he is able to use all 4 'bars' on the current task. One way to do that is to use a 'work station inbox'. His own in-tray with an out-tray. Each task put in a separate tray, so that he can simply work his way through the tasks.
Build up his confidence, by setting tasks that you KNOW he can do. And take away any 'red herrings'. So, for instance, if a child was at the level of ordering numbers, you would give a task that had the numbers 1-5 on one side, and spaces on the other. No extra numbers. Just keep it simple. Then the child focuses on what needs to be done.
I know that short-term, work arounds seem to be a hinderance. But long-term, they can be really successful.