I've taken a habit to request there when I'm SL and providing these when I'm CO. Haven't found a thread about it so I figured it was an idea worth kicking around.

We know the average Battlefield CO is a strangely psychic guy. He's able to spot enemy infantry and vehicles even if he just clicks on a random spot on his map. You can use this ability to quickly inform of hostiles at a particular location. Usually, a CO does a string of critical spottings following the SAT Track blips, but the fun part is that you don't even need the blips.

Situation: A SL and some buddies are making their way to a flag. They want some intel to know just what they're diving into. Does this warrant a UAV? Nah, not really - most of the time, it reveals a lone infantry, or worse, nothing at all.

Thus comes the "spot check". Right-click close to the flag and select "spotted", once or twice. Any enemy infantry or vehicle that's alive will be detected by the spot and shown on the minimap, giving the squad a rough idea of enemy locations. If nothing's found, the usual question marks are displayed.

The reason I want to talk about it is that oftentimes, I come across a flag that looks obviously deserted. I don't want to comb the area for hostiles and a UAV is overkill - but I don't want to get surprised either. Thanks to a spot check, I'm able to quickly know if there are hostiles and which direction they're in.

I'll stop rambling and just get to the tl;dr part:

1) The squad leader says over VoIP "This is 1, Requesting spot check, [silo 5/ruins flag/my location]"
2) CO quickly right-clicks on the designated location and selects "spotted". Usually twice to cover both sides of a flag, maybe a third time if the immediate area is large.
3) If enemies are found, zoom in, assess the situation, and supplement with a UAV if necessary.

Note: CO acknowledgement is not necessary unless he's not in a position to immediately spot check, but wants to let the SL know it's coming up in a moment.