George wrote:

1.15mm plus 3mm is 18mm thats high enough cut for a BJ

15mm+ is reasonable for hardwood flooring, but most of us encountering
this problem are doing it for laminates that are thinner than that, too
thin for a biscuit jointer.

2.You dont drag the BJ along you do two plunges on the architrave and chisle
of the bottom piece after you have cut through the wood as you would do with
a FM.

If you're just doing the architrave, then maybe. I certainly wouldn't
like to do a whole skirting by repeated plunges (or by dragging).

Estimated time with a BJ with minimium effort
5 sec,

I'm so sorry for you. Maybe more effort and it'll last longer?