Reassess engine move

I play games I blunder in the opening training exercises, using the highest-level engine on the site. I then ask for an analysis of the game. This helps me learn why a move was bad.
I found it a bit odd to discover that the master leveled engine made a mistake on move 5.
http://en.lichess.org/t9OkHKxw/black#8
This means, since they can make mistakes, they could also make imperfections. Has anyone discovered engine blunders at level eight?

For an explanation, I believe AI 8 gets 0.5 seconds and evaluation 4 seconds per move.

Yes - there is a difference between Stockfish Level 8 and the Stockfish used for analysis - that one takes longer, so it searches deeper and therefore finds mistakes SF level 8 makes