Now your starting to understand why I love iffy signals. Many of the smaller Roman Coins I dig are in that range. It takes time but it is simple - Good Sites = Lots of time digging as much as possible. Then returning & digging more, until every nail is gone. Yesterday, I cleared plenty of Roman Nails, but I don't do that on my first grid over, as its too time consuming. As the years go on, I get less & less fussy. If its ploughed land, you can then start to judge how much new material has been turned up. If you just 'cherry pick', not only do you miss some great stuff, the next year you 'hear' all that crap you left, & guess what you hear the year after that & so on.
PS. Bear in mind, I use a 'hear everything' setting when discussing the above. ie. No Disc.