Reading the tweets on the Twitter session on Blended Learning was like being given new prescription glasses.  Everything that was blurry before suddenly becomes clear. 
However, there were two threads of discussion that I still struggled to understand. 
Firstly I did not quite understand the concept of “Social Presence”
The participants wrote the following tweets:

What is “Social Presence”, why is it important, how does it work?  Without social presence, will the students still be learning effectively?

This posting answered many many of my questions, and I certainly hope you will find it useful, too.
My key take away: Involve The Student.  Actively rope them in as an active participant.  Many tools are available to help us do that and one of the most powerful is “Liberating Structures” shared by my very wise group member, Sarah Franke.  Thank you Sarah.
Secondly, I struggled to wrap my head around “What about the principles that should guide your design thinking”. 
I found this diagram by Connie Malamed to be very helpful in answering this question. 

You can read more about her approach to instructional design based on design thinking principles here.
Finally, on the issue of feedback.  Much was discussed during the tweet chat and I would like add the analogy of the four steps of learning to play tennis when giving feedback to this discussion. 
Step 1 – Demonstrate
The coach demonstrates a very specific way of serving.  All the students watch carefully. 
Step 2 – Practice
The student steps forward and repeat (practice) what the coach just demonstrated.  
Step 3 – Feedback
The coach gives immediate and specific feedback on what the student did right or not right enough, correcting the student until the desired way of serving or doing something is achieved. 
Step 4 – Practice, Again
Before the coach moves on to the next technique, the student practices again and again right there and then to “get the hang of it”, each time with the coach giving timely and precise feedback. 
It is such a simple approach that I am sure your grandmother could have told me so.  Well, I am glad she did.  Thank you grandma, and happy playing! 

Social Presence & Design Thinking In Instructional Design