The sidebars everywhere hack is only checking what the users default style is, not what style is currently in use. Also, it is checking on global_start which happens before the mobile detect add-on does it's business and possible changes the style, modifying that particular plugin would not work anyway.
If you are using the
Lightweight style I wrote, try installin the Lightweight STyle Options addon and add the line
Code:
// disable ESB
global $bbandSBactive=0;
to the disable add-ons section