What is 'weight' and what is to be done?

Why do we value knowledge?  Because we like to learn from it, and learning enables us to do things - one of which is to understand a bit more about life, the universe and everything.

What is my practice?  What do I actually do as a filmmaker?  This is an important question for me to answer because it may help to justify the funding of a PhD, which must be a 'significant and original contribution to knowledge'.

So, there is knowledge produced through creative experimentation in the processes employed in filmmaking.

Where does this knowledge show itself?  In documentation of the processes - which can be read and followed by other filmmakers.  And in the artefact produced -

How do you learn to do art?  You look at lots of it.  You think about what you have seen.  You compare it to what you do.  You analyse the differences.  You practice.  You read about how artists do it.  You copy emulate them.  You do it.

A 'significant and original contribution' must be a useful guide to others in your field.  Two questions can be answered:

How do you make films?(practice)  Thesis       'This is what I do'.
What is filmmaking?      (theory)     Antithesis  'How does it compare with others'
Look here!                      (my film)  Synthesis  'Learn from this'.

My film is the embodiment of my practice as informed by my thinking about the theories of film making.  If you can learn from something, it must contain knowledge.  My film shows what a film can be, and how a film can be/look/sound.  Knowledge what and knowledge how.

HOWEVER -
Your practice might be ill-informed, lack technique, be unreflective.
Your ability to theorise and show your understanding of theory may be poor.
Your finished work might be boring, derivative, uninspiring.

In other words, there may be nothing (new) to learn from it, so although it could be claimed to embody some knowledge, it lacks usefulness, so is insignificant.