Bull or not you simply have to live with it, there's nothing to do.
And if you do not like the movement bonus, mod it;
In your data-folder open the file descr_campaign_db with Notepad++ that's a free program you can get here: http://notepad-plus-plus.org/
Look for the crusade-section
Change the movment bonus (in red), make it 1.0 if you want no movment bonus
Code:
<crusades> <required_jihad_piety int="5"/>
<max_disband_progress float="5.0"/>
<near_target_no_disband_distance float="4.0"/>
<disband_progress_window float="3"/>
<crusade_called_start_turn float="40"/>
<jihad_called_start_turn float="40"/>
<movement_points_modifier float="1.75"/>
</crusades>
Save.
Saved game compatible.