I have a two-part question. I have read in several places that FUs can not be placed to close together. If this is true then why not?

My second question is; I have just had 2400 FU grafts done by a well established doc mentioned on this site. I am a class 5. Would each graft always have a scab. I have not counted them, but it does not look like 2400. I was wondering if there were grafts that were planted that I probably can not see.

I am not doubting the doc, but this is all new to me.