obstruct.01 should have an instrument argument, like block.01

[nschneid]

obstruct.01 currently has 2 roles:

<role descr="blocker, obstruction" f="PAG" n="0">
          <vnrole vncls="67" vntheta="Agent"/>
        </role>
        <role descr="thing obstructed" f="PPT" n="1">
          <vnrole vncls="67" vntheta="Theme"/>
</role>

I think there should be an instrument role, similar to block.01, e.g. for "I obstructed his view with my hand".

[nschneid]

(This came up in a Little Prince AMR.)