I also agree that the timing of FT steps in events such as WSS are not off time. Here's my take of how, in general (underlined), the timing works. Instead of counting SQQ, you need to count 1, 2, 3, 4. In fact, it's probably better if you count &1, &2, &3, &4. What you're trying to do is take the first step using the full measure of the slow, that is, on count 2. So after the preceding count 4 (step 3) where you are up, you are doing a lowering action (downswing) on count &1 (step 1) and doing a rising action (upswing) on count &2. You stay up on counts &3, &4 (steps 2 and 3) and then lower into the next &1. Now I'm sure there is artistic license by some people to modify the timing of certain steps in FT, but in general, I think this is how it works.
Why do they time the FT is this way? I think it's to make for a more constant motion of the body through all the steps. In general, the first step is longer than the last 2 steps. If your body is moving at a constant rate through all 4 beats, it looks like you are floating along as you do the foxtrot and it doesn't look like your horizontal speed is varying that much. Now I know a lot of people do step on count 1 of slow in FT. Most noticeable in American style continuity FT (Silver and above). You see that a lot at comps. It's not clear to me which count (1 or 2) is best to step slow for American continuity FT. If you were at a comp, since most everyone is stepping on count 1, maybe you should too? But for Intl FT, stepping on count 2 is more universal I think.
Don't know what others think about this, but this is my take on FT timing.