Well it depends on what brand you have
and the specs but basically if you do what clam digger said you'll find it will resignate the fish [or as the fish finder designates them "X,Y gid" submerged objects] as just objects. Ff the fish are schooled as you said the grid divides it self up on the screen [you dont see it] but the fish symbols dont change with the grid size so your not getting a truly accurate reading on fish location within the school but it gives you an idea of shape and depth at depth the fish finder finds the fish harder to designate on the grid and may confuse it thus the tail to tail thing [only applies when tail to tail party is a straight line]. S since the fish finder cannot designate between species [gird division, chaos factor (hehe)] go by patterns of movement and depth. I can answer uestions on those if you have them.
