OK Terebus, since there is no point in arguing who is or is not a liar let's look at it a different way.

You have missed an easier way of pushing my grandfather's (correctly reported, so far as memory allows) perception out of the argument,

I can't be sure if his simile was critical of the generals or not. It could have been a recognition of what top military strategists have to do. Maybe it was frustration rather than despair. It could have been disgust though.

In written history, as on the internet, personal experiences allow a reality check.