I'm going to say this once and for all.
I might agree that this device wouldn't help at all.

But it's still up to the seller to sell.
there's lots of automotive product which is in the market and IMO no use, but everyone is still selling and buying. Willing buyer concept.

If you guys do not like it and felt that it's no use; than stop jeopardising a sales thread.

If you guys really want to, start a debate in F&F which I think there's already multiple topics on this sort of products!

Another replies after this deemed to be "jeopardising" and threats to the seller would get a suspension of 7 days! and I meant it!