asudoh/dojox_mvc — comment on commit 5150504c50b1b08c8196eb2192e29a5fb10b379f
File: Bind.js line 152
By asudoh:

The intent here is keeping the same behavior with other dojox.mvc code (code supporting older ref syntax). Such code does model -> view copy as part of initialization unless the value is null/undefined. The copy upon data change in model/view is done, even if the new value is null/undefined, as long as there is a "change".
Personally interested in the background of original "initial copy" code, too.