As I understand it there are some limitations of the scrolling speed in the browser - but if this is not correct I'd recommend speeding up the scrolling a bit.
In addition I find that scrolling doesn't always react as I would expect. Again, this is likely a limitation of the web app, but I thought I would bring it up. As the scroll momentum slows I typically attempt to scroll again to speed it back up - this often stops the scrolling completely, unlike a native app.
Also, juts wanted to give Kudos to you guys. The app is extremely well done and I still intend to use it in spite of the changes google put out last week with their web app.
edit: just noticed this is a 'known' defect