Research on properties of effective feedback
Here are a few theories and sources I happen to know that relate to your questions:


Contextual cues aid recall of context-dependent memories. Plenty of research exists on these topics. An easily digestible example may be found through PsychCentral (Nauert, 2009).
We have another great question about context-switching here already that you might want to check out: https://cogsci.stackexchange.com/q/4993/4086
Haven't got much to offer in response to this question beyond the suggestion that you see what they have to say about it over at the User Experience Stack Exchange.
Theories to support your theses 4.1 and 4.2:


This idea seems to relate to the primacy and recency effects in memory, which promote recall of first and last items in a list, respectively. Here's a graph from Wikipedia that combines these ideas into the serial position effect:

(source: wikimedia.org)  
Haven't got more to add here beyond the link to the other question I mentioned in response 2. I hope you get some other, helpful responses here!



Reference

Nauert, R. (2009, December 14). How cues and context help memory. PsychCentral: Psychotherapy News. Retrieved from http://psychcentral.com/news/2009/12/14/how-cues-and-context-help-memory/10159.html.