blu mentioned in another thread that the footsteps are missing as Herb and Dan walk back toward the bum behind Winkie's and then I noticed that when the footsteps appear - it's not two sets of footsteps ... it's only one.
So, that got me to rethink things a bit particularly around the question, why only one set of footsteps?
How about this ... there is only one set of footsteps because there is only one person walking. Herb.
Herb and Dan's scene within Winkie's may be someone's dream but it's a dream about a delusional man with an imaginary friend named Dan.
Key points:
1. We don't see anyone other than Herb interact with Dan.
2. Herb pays the diner bill.
3. Herb opens the door when they leave.
4. Most importantly, Herb can talk with his imaginary friend Dan. But he can't get him to produce footsteps and he can't get him to eat the food he orders. Dan eats none of the food or drink before him nor does he even use his napkin. Herb chows everything down.
The downside of this idea would seem to be what's the point of a dreamer dreaming about individuals living in a fantasy world (so to speak)?
Is it possible that Lynch is doing his version of Harvey (1950) during the dream portion of the film? Where only some people can see the white rabbit? After all, in the second Winkie's scene - Betty is given the check. Why would the waitress assume she gets it ... unless she is the only one actually at the table? We sure don't see Rita even react with any physical item at the table - let alone eat something or any real sign that the waitress really sees her. Food for thought.


