"On the fourth beat count 4 (and) That's your lowering in the neutral position and the flexing of the knee ready to punch off into the next step. If you try to lower whilst your none standing foot is still to the rear. The following step will be weak. This might suit a Social dancer but not a competition dancer."

Actually this lowering while the trailing foot is still trailing is exactly what top comeptitors do - their arriving foot is flat before the trailing foot has closed. The do not get stuck because they continue to bend the knee as the feet collect - though the good ones have their body already beyond that foot before the trailing foot finally passes it.

Quickstep. Thinking that someone you have not seen dance is lacking in technique is just to show your superior knowledge or so you think. I prefer not to under estimate someone I don't know. It does not stimulate good conversation or thaught. Just because someone ask a simple question does not mean that they lack knowledge on the subject and wish to be preached to.