IMO, keep it short if it is something common. I mean if you shadowed a doctor, they know what that involves so keep it simple. If it is something you think is unique, such as starting a non-profit group, then you might want to give a lot of detail so they know exactly what you did. I know if I was reading an application that went into too much detail about something really basic and common I would go into "skimming mode," and maybe even just skim the rest of the application. Now, I'm not an ADCOM, but they have (or in our case will have) hundreds of apps to read through, and 1350 characters abou shadowing may make them disinterested in your application. Again, this is just my opinion, and this will be the approach I take to my activities. Anyone with experience care to comment on this?