Hi Pilou, your solution looks good!

I'm not that used to Push/Pull in SketchUp so it doesn't really occur to me to use it like a boolean to cut something all the way through, but it does work fine for that.

Only 2 problems - #1 you're using a plugin instead of the "stock" SketchUp! (the solution in MoI is only using all standard built-in tools), and #2 - you appear to have extra edges in your result running down the middle of the model, I guess to get a fully clean result those would also need to be deleted as an extra step?

Also how long does it take?

Here is a new record from me, with some faster mouse clicking I get 59 seconds: