That's what this video is saying. No mention of that so far in the PSP software. This advice is reiterated, after a fashion, at the bottom of this page. If you can get by the rather irksome attempt at folksy prose, this is a very good source of beginners' exercises.
This looks as if it's a bit further down the road, but I found it whilst googling my way to the fingers-laying-still-on-keys business. I found this white-cat-black-cat video on this site here. I like the teacher's accent.