I never had the intention to become a Fitts' law expert and I still prefer to do something else. However, as a scientist I am obliged to truth.
This are my publications on Fitts' Law:
Only One Fitts' Law Formula - please!This is my contribution to a scientific HCI community. It is a 60 page PDF document (1.6 MByte) from June 2023:
My critzism in short (two figures):
A brain is not a channel according to Shannon's definition of a channel.
It is not the case that the eye sends a signal to the hand and the brain adds disturbing noise.
In consequence Shannon's theorems do not apply.
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Why is according to MacKenzie still some difficulty left when the pointer reached the target edge and the task is fulfilled?
The old lecture from July 2013 is still available but obsolete. It is a 31 page PDF document (0.97 MByte):
A Lecture on Fitts' Law