It starts with projection based on where the Rams are likely to slot Turner and goes from there. They still may opt for Newton or Murphy if they like the DL combination overall with Turner opposite one of them more than the other way. Maybe that feels better to them than going Fiske later on or one of these others who look like 5T or NT. There is room to think they covet penetration and perhaps aren't so tied up in conventional traits for the different DL alignments.
But it seems to me if they can hit on that Edge with that top pick then find a couple big bodies to fill around the primary rush threats they would be better off than taking a 3T up high and then a project rusher.
