Sounds a bit similar to how on etoro you can set your portfolio to copy the activity of other people on the platform (past performance is not a guarantee for the future 
) but I guess this way it will crowd source freetrades activities for the platform users to follow an etf. Trouble is as the portfolio expands we will basically have people invested in every share out there so will essentially come down to being just shares that have increased in value by 7% but on that criteria at what point would a share get sold?