Hi uys. i am a newbei. so please don't angry :/
i bought a new xbox 360 (it has 1.7 fw) i didn't connect live server (i will not). i don't want to take a risk...

here is my question; one day maybe i'll want connect to live server. that day can i restore to original fw and connect to server without problem?

You can restore back to original and should be ok assuming it is LT(1.7) that you have got as thats said to be undetectable, if it was a previous firmware these are detectable and the nand chip stores info so this would not be safe

Has there been actual "proof" that we need to flash back to stock firmware from LT before applying system updates?

I dont think theres any proof as such, but its advice from the dev team and they know what they are doing obviously

Slick wrote:I dont think theres any proof as such, but its advice from the dev team and they know what they are doing obviously

I do assume that this caution of flashing back to stock would apply to system updates via Live & not from USB/DVD