> users should go through an extra step / give large amounts of trust If it's a webapp, then you have to trust that the application won't disappear overnight,

> users should go through an extra step / give large amounts of trust If it's a webapp, then you have to trust that the application won't disappear overnight, or be changed it ways you don't like. If you have downloaded the software, you can continue to use it. There are trade-offs in both directions.