Combination hierarchy List vs. Alt Hierarchy List

Hi,

After watching the Hierarchy Design and Combination Lists video, I have the following question.

Are combination and alt hierarchy lists the same?

When I am faced with the scenario described in the lesson...
Product Hierarchy:
|-- Product Family
   |--Product
      |--SKU
Account Planning:
|-- Account

   |-- Product

I use an "Alt Hierarchy" with the implementation mechanism differing slightly from the Combination implementation mechanism in the video.

Any idea?