is charting self fulfilling

just wondering what others think about the benefits of charting, which is based on 'yesterday's'data

ie - certain signals are triggered and all those chartists jump on or off whatever stock has been flagged, thereby fulfilling their own readings of said charts

lol - would be interesting to have seperate markets for chartists & non chartists

and puullleeeeze, take this in the light manner in which it is intended