maybe this should be in 'chat' but since all references I have made to "know-how" has been made in the main forum, I post here.

I have, numerous times, referred to "know-how" as a prerequisite for certain designs to succeed, notably switching power.

Now for an example that just came to me last night.

In our previous house I installed a Jacuzzi bathtub and enjoyed it immensely, I just wondered why it was not as deep as I would like it to be. Then when we moved, and I were to replace the tub in the next house, I found another brand with the jets in the same place, the pump the same HP, and higher walls. So, of course, I bought that one. That tub is not even half as enjoyable as the Jacuzzi.

So with the 'design' being the same, the "know-how" different the one made by the people with the "know-how" is a great tub, the one made by the people without the "know-how" is not.

Erik