Back in May 2013, during a Webmaster central hangout with John Mueller, John confirmed that Google treats internal 301’s to the homepage as 404’s. That should mean that if you 301 internal pages to the root, they won’t pass PageRank. However, this can still be interpreted incorrectly as there are many questions that remained unanswered.
For example, if example.com/pageA has 100 external links, and subsequently 301’d to the root example.com, does that mean that the value of these links are also gone?
What’s your take on it?
The conversation starts around the 22nd minute in the video below.