Not directed at your post, but bouncing off your post with regard to the issue of "trees" in the way of one of the SS countersniper teams.
Whatever the size of the trees or number of trees, the SS would have had to do a thorough walk-through and analysis of the perimeter and area around the perimeter and if there was a roof in line of sight of the stage and podium, then they would immediately have known that it was an opportunity for a sniper and therefore needed high security. The Acting Director of the Secret Service said today that he went on that roof and lay in a prone position and said he felt ashamed.
He didn't say there was a tree in the way, but that he felt ashamed. That says it all, imo.
He also said they discussed with local LE who were going to be in the adjacent building that they needed to watch the roof of that building from their position.
Those snipers should have checked the roof from their window and alerted SS immediately as soon as they saw him. They already knew there was a strange guy outside who knew they were there, after being alerted by the local LE who left at the end of his shift.