SC 2.2.4 vs. SC 3.2.5 and techniques G75/G76

Well this is late in the day but I thought I'll express my concern anyway. Better late than never. It can still be addressed.

SC 2.2.4 Interruptions: Interruptions can be postponed or suppressed by the user, except interruptions involving an  emergency. (Level AAA) 

SC3.2.5 Change on Request: 
Changes of context  are initiated only by user request or a  mechanism  is available to turn off such changes. (Level AAA)
Comment: 
3.2 deals with making Web page content behave in predictable ways and the emphasis is on consistent layout, navigation and identification. This is in keeping with the "understanding" principle. 
I believe a change in context caused by  auto updating content (3.2.5)  is covered by interruptions (2.2.4) that  upset task focus. Such an interruption or change in context makes it difficult to operate (or even read) the Web page. So change of context by auto updating content is a transgression of the "operate" principle than the "understand" principle. Difficulty in understanding posed by auto updating content is a consequence of difficulties posed during operation.
On the other hand, changes in context referred to 3.2.1 or 3.2.2 are also unexpected but are based on user action (focus change / form input) and certainly hamper understanding. As a consequence it makes operation difficult.
The supporting techniques for 2.2.4 and 3.2.5 too are identical:
G75 for 2.2.4: Providing a mechanism to postpone any updating of content
G76 for 3.2.5: Providing a mechanism to request an update of the content instead of updating automatically

I think this is just a play of words and  both SC 3.2.5 and technique G76 can be deleted without any  loss.
Thanks,
Sailesh Panchang
www.deque.com
spanchang02@yahoo.com
Tel 571-344-1765

Received on Thursday, 10 July 2008 20:23:00 UTC