At first, couldn't understand and was around 430. Now, I slowly progress:
401... 391... 381... 375... 371 means 28 off.
26 off... 20 off... 18 off... 14 off... What a work!
** one year later**
Still working on it once in a while. Stuck 14 off and no more ideas.
awww... 10 off... there is hope... :D
5 mins later: 8 off and the way I saved 2 more gives me some hope as what to search for...
I was right: 2 mins later, 6 off.
That level is enjoyable, but I'm stuck 2 off since ages and can't find how to cut... grrrrr...
** one year later **
Back to it yesterday, got back my 2 off and was stuck again. I thought I know where I can cut so I study and finally saw it: just a wrong choice of exit, although apparently equivalent. So simple. I was just blind.
So, a little hint: if you're 2 off and stuck, your route is most probably correct, but somewhere, you go through one way because it seems same than the other, but in the end, it's not. :D
Insights