If there is html block, hope to include php block
It should be possible to change the html block to be only visible to admins and to avoid the check for php.
There is a modified HTML block that only appears to admin users in this thread
http://moodle.org/mod/forum/discuss.php?d=26951
I use it to place normal hyperlinks to other pages that contain PHP maintenance scripts.
I had not considered disabling the PHP checking in the block.