Hi Burr well I don't know how Loft could construct a surface without poles in a case like that, you have to use an extended and then trimmed surface like you did to avoid poles.

The drag points are for the case of lofting or blending between closed curves, where you can control where the seam edge of the closed surface will be at. It can't really apply for the one single closed curve case though.

- Michael

Thanks a lot Burma and Michael.
I've tested the twice and in my case, the boolean way is the fastest solution.
Thanks again !!!