Delete SCOM (2012) override with Powershell

Please give me detailed and working example how to delete multiple overrides with powershell. I know there are examples like:

 $mp=get-scommanagementpack | where {$_.Name -eq 'MP_name_goes_here'}
$mp | get-scomoverride | where {$_.Name -match 'name_goes_her' -and $_.Value -eq common_value_goes_here} | %{$_.Status=[Microsoft.EnterpriseManagement.Configuration.ManagementPackElementStatus]::PendingDelete}
$mp.AcceptChanges()

But that is not working! I have a feeling that you can't delete overrides with powershell because there are no working examples.