Bow and arrow stance question

[Polymorph]

Hi
I'm watching the long fist DVD and have a couple of questions.

When parcticing the stances, you turn into a bow stance from the horse stance and the heels are inline.

When watching the form it looks like their heels are not in line, are they about 1/2 shoulder width apart and about a horse stance width long?

Also I get the urge to pivot on my toes rather than heels, is that okay?, does it matter? what benifit is there pivoting on heels?

Thank you

[DavidR]

Dear Polymorph

You will probably have better replies if you post your question to the training or shaolin topic.