I read this on a previous forum and it came to my attention. I know 
"Assault and Battery" is a lock on and will chase the target down UNLESS the target teleports or recalls a considerable distance away. What if 
went... 
and E'd. Would he get away?
So, this made me curious, so I did a quick bit of experimentation.
First thing you need to know is that it is indeed possible to break Vi's ult by getting far enough away. It's not the act of teleporting that does it, but the sheer distance created.
Second thing is that to actually pull that off you need to be going really, really fast.
How fast you ask? Well, about 2600 units a second, assuming Vi ults you from her max cast range and you start running away at the exact same moment. That '6' in there's a pretty important number by the way, turn that into a 5 instead and you'll only be running at 2500 units a second. That means Vi will chase you across most of Summoners Rift before finally punching you. She just keeps accelerating, so you need a lot of sustained speed to hit escape distance in the time you've got available before she's faster than you.
So, how does that number compare to a Hecarim with Ghost as a summoner spell, maxed E and ? Well, when standing on the fountain with Homeguard constantly refreshing that'll get you to about 2000 movement speed. Not bad at all, but definitely not fast enough. Use a Powerballing Rammus with a Zilean assisting him on the other hand...
No. Since he did not teleport, she would follow him the entire way. This would still work in Hecarim's favor though if he did it right, as he could take her far away from her allies before he fought her.
"Vi stands for virtually no escape"
A bit stupid, don't you think?
