Thanks for the clarifying statement on Indian clothing, ji. I'm only going on what I've read about kachera so far. Perhaps I haven't been reading the right sources.
And I may have worded my spiritual advancement comment wrong. What I'm trying to convey is that becoming Khalsa is seen as a more devout state within the Sikh panth. That is my understanding. And to be Khalsa, you have to wear the uniform. And the uniform is for men - there is no separate uniform for women that I can tell, so we wear the male uniform. Which includes the male shorts. Which become an undergarment for women and, these days, most men who wear pants over their shorts.Reference:: Sikh Philosophy Network http://www.sikhphilosophy.net/sikh-sikhi-sikhism/14434-kacheras.htmlReference:: Sikh Philosophy Network http://www.sikhphilosophy.net/showthread.php?t=14434
So the question really needs to be, what is the purpose of kachera and how should they be constructed to a) still be kachera and b) be worn as an undergarment?