If a flood of even well intentioned helpers rushes in... you can have big overlaps in your search..and rescue..
To be systematic there must be control...and one man in charge not fifty..
Distractions of having to intercept others in your search and rescue area slow the whole process down
Chertov put it best...'We're following the General"
Great advice
Extras need to hang back and wait until they are called upon and then they can be efficiently folded into the organization
imo
Not to mention tons of volunteers with dysentery, e-coli, etc...