Have not had this problem would point out that do to clash graphics what you see is not always what the games sees for a couple reasons.
3/4 perspective doesn't let you see distance between object clearly.
If you have 2 giants or golems stacked i one spot and the xbox pops one its easy to miss is there is another there.
This would cause a re target.
If this was a common glitch or new AI it would make tanks pretty useless...

