Of course it matters...why do you think it is done every single day. Look at the chart to see how that constant struggle is depicted.
It affects investor sentiment and the TA...serves to actually manipulate the action on a small volume stock.
You said so yourself...
"I sold I don't know 20,000 shares. I greatly clobbered the bid and my agenda is entirely personal."
The volume is scant right now so 500 shares bumps the close to a much higher price which 'helps' the chart. Same as if the opposite happened everyday with a selling tape painter. The b/a would get shaken down on low volume.
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