You seem to be conflating two different discussions.
The OP is not talking about the progress bar as an indicator of page loading, like the other discussions on HN recently. Instead, he was mentioning someone's suggestion that it be used like a scroll bar to mimic the progress of scrolling down the page.
The OP is not talking about the progress bar as an indicator of page loading, like the other discussions on HN recently. Instead, he was mentioning someone's suggestion that it be used like a scroll bar to mimic the progress of scrolling down the page.