Yes, if it can't see it then it can't shoot at it.
My example was a bit poor - though I know you're answer is the same...
The reason for my confusion was because I had a T80 behind a hill. It was actually the Yellow Order - so for Effective Range - and the first part of the order was FIRE - which it couldn't do because there were no US units in LoS. However the next order was a Move and Fire and had I moved, I would've been able to fire. So I thought I should play that - then I was thinking "But he doesn't know the US are there...."
There are also other examples (that make you think LoS doesn't matter), particularly in the Secondary order group - something like Move Towards Closest PU. This is also the case on the Counter Actions sheet.
I guess I'm asking for confirmation that LoS matters in ALL these orders or whether LoS is only taken into account when being told to fire or move and fire.
Here's an example of a Counter Action
AEO closest to PU thats Fired - Fire or Move towards
- is LoS required here or just simply as said -
closest PU that Fired?
I think it's hard for me sometimes to translate the orders of the Solo Assistant because I'm not sure if LoS is a prerequisite. If LoS is required for all Solo Assistant orders and Counter Actions when a Player Unit is specified, then I'm good and that's all the clarification I need.