OK thanks again. Here's a save which shows the situation on Turn 6, one turn before the Merkava (C2) got whacked by a side shot. (After it fired on an enemy unit to the southeast I neglected to face it forwards again; nor did I bother to fire dischargers or smoke rounds just in case. Talk about criminal negligence!)
At this point the Scout V0 is within 25-30 hexes of the T-12's, which are deployed as a battery just south or west of the depression at 66,4, 65,3, etc. (they're around hexes 60,6, 59,3, 59,7--can't be precise 'cuz the game won't let me enter as human on the Russian side). All are in plain earth terrain.
Both scouts and snipers were moving (running?) at 6 mph, so they didn't see the unit which fired earlier that turn at AE0, the Nagmachon moving 10 hexes ahead of C2. (I'd planned to bring the APCs in line oblique to it back to pick up the foot-slogging core infantry, but ditched that idea after AE0's close call. Which makes my failure to protect the Merkavas even more inexplicable.)
Let the game run through turn 7 without firing or moving anything to see what would happen. This time both rounds (one shot, one missile) from one of the T-12's (at hex 63,5) missed, and it was spotted! So it would seem that moving has a decidedly deleterious effect on spotting, as one would expect. The game system stands up under close scrutiny yet again
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