I think you misunderstand my point. The amount of time I looked forward was about the amount of time it takes to release and depress the hatswitch. The distance is deceiving because it reads 1500 until they are 1000 out. Or at least that's what I saw. Hence no way to tell closure rate.
And if your system is that good that you can tell something is getting closer and at what speed that's happening. Terrific! Mine isn't. All I saw was a dot.
No, it depends. It's got nothing to do with system specs.
...
You look behind, see a bogey at you which reads '1000'
Okay, how fast is he coming in? Obviously, it's not hard to guess if you have been tracking his movement since he was further out. Over 1000 yards, the distance changes in increments of 500 yards. So how fast it changes by 500 yards, gives you the general idea of how fast it is moving, by observing the "500yard ticks".
But if you didn't notice him before? Then obviously you have no previous knowledge of from where, and how fast he closed in. You have to wait and see how fast it changes by 200yard ticks.
I presume it's the latter case you have problems with - and basically, that's how it should be. Having just one glance at a bogey behind you at dangerous distances like 1000yards, and immediately being able to judge relative E status by the "countdown" in 1 yard increments, is a too big of a crutch.
Again, if it's going to be there make it usefull. Else, get rid of it completely.
It's useful - gunnery is harder, judgement of distance is more difficult, and close-range fights are lot more exciting.