Not a good thing... You will never get her to explain it the way YOU would like it to be explained... It will only arise more questions... And I don't think any woman is capable of discussing detailed sexual encouters without watering the shit down...
it is bad advice all aroud dude. Today she might say "Oh I was so shy I asked him to keep the lights off, and I never looked at his penis"
then a couple of years from now you might be at a sex shop and she'll say "Oh get these condoms with the studs on them, I have used them before... they are great"
You: "Not with me I have never bought those"
Her:"ummm...ahhh... Well you know about the other guy before"
you:"We'll you told me you never looked at his penis how do you know what kind of condoms he used"
Her:"Well one time I used my mouth to roll it down his cock just for fun"
You: " I thought you said you never had oral sex"
Her: "well it was just a few times and he always wore a condom when I performed on him"
>>> 6 Years later >>>
Her: "It's ok Baby I don't mind swallowing you cum... I have tasted worst"
You: "I though you said he always wore a condom when you sucked him off"
............