I know I am opening a can of worms,but many top dancers will close the foot in the Waltz slightly ahead or back of the other to ensure the their dancing is progresive. If you don't believe me take a look at Gleaves teaching vidio where he demonstrates the basic waltz the same tape that he says to count the halve as well as the whole beats. In a lock step it's common to see people place the third step in a possition where they have to move back befor going forward, I think this why they now call it a cross step?.

Feet must close perfectly parallel on the rise, but should already be apart (but with knees still close) by the time the standing heel touches the floor.

Many advanced dancers use a minimum number of foot closure steps however.

Suomynona. Michael Barr very recently said. That it is nice to see the basic 1 2 3 being used instead of syncopated and passing steps with the timing of
1 & 2 & 3 & Very refreshing was said.