Growing vanda roots upside down

[Kollba]

While I am here I can as well annoy you a bit more with another question.

I have earlier complained that my vandas are not very eager on growing new roots.
I saw a couples of movies on YouTube where people were hanging their vandas upside down when they had almost no roots at all or just one little tiny root.
I do not remember the words they were using but the explanation was something like "the growing hormones (or energy ?) that the plant is producing is striving upwards so if you hang the orchids upside down it will help the roots start growing"... Or something similar.
Is that true ?
Does anyone here have any experience from doing this ?