We are not exactly sure of your idea and what do you want to achieve, but we have created a simple project to illustrate our idea. Please check it and if this i not the behavior you want, send us a project or give us more details what is your problem.
We were wondering - how did you implement the Behavior: "SetGridItemAsCommandParameter" - did you use Blend or something else?
Hopefully the attached project helps.
All the best,
the Telerik team