All it says is he would upvote it to where people could see it (trending) when his voting power is 100% (aka. mana), he did not say he would give a 100% weight upvote with mana of 100%, just that his mana would be at 100% power when he voted and would make sure the vote got the post to trending.
Vote power is not the same as vote weight.
I looked at this again a little while ago with some help and saw where I had misunderstood, but thank you for the reply, I always appreciate another voice to help clarify things (spend too long staring at the computer and you never know what will confuse you next! lol).
Thanks again :)