Is it X-com or X-com 2 where you can hold down the Alt-key and it'll give you a preview of all available targets from that cover? If so, they should probably utilize that skill. It's a life saver when you need to flank a target.
I'm not sure if this works in X-com 1 (it does in x-com 2) but if they press ALT when mousing over locations, you can see which enemies are visible from that position. It makes it easier to flank enemies from various points of cover.
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