You can't really train to handle opening gates. It damages your body either way depending on how far you go. That is why Guy couldn't move after opening the 7th.
They are on equal footing but Kakashi is considered the better of the two since he was considered for Hokage.
Actually you can. That's why Gai can withsand the effects of the gates moreso than Lee can. Gai was still able to withstand the effects of the 7th gate until after the interrogation of Kisame, which happened sometime ago after he opened the gates to defeat kisame.
In terms of raw speed and power, guy outclasses kakashi completely, but in terms of ninjutsu prowess and intellect, kakashi has guy beaten.
Futur3Cha0s said:
t is impossible for it to be a groundless statement if it is known that he can at least open one gate. for it to be groundless he would have to not be able to open any. then it would be a complete speculation that he can open them and therefore a groundless statement. taking what we know about kakashi (he can open at least one gate) and combining it with his motives (he wants to get stronger) then we can make a groundful statement that he can open more. he can open one therefore he might be able to open more, that is not a groundless statement. the only groundless thing here is your assumption that he cant open more.
We can only go by what we are shown in the manga for now. Until kakashi shows that he can open more gates, then he will only be able to open the first one.