Fool's Mate

What is the shortest possible Lasca game, assuming an inept opponent?

Lambert Hergesell and Detlef Steuer have contacted me with a set of 7-move mates, beating the 8-move mate found by Bruce Wilford, previously reported here as the best solution.

Here's one of their games:

1. c3-d4 e5xc3
2. d2xb4 f6-e5
3. e1-d2 g7-f6
4. c3-d4 a5xc3xe1
5. g3-f4 e1xg3
6. g1-f2 g3xe1
7. c1-d2 e1xc3

White is blocked in and cannot move:


They are confident that there are no shorter solutions.