It hooks more than Motiv's chart would lead you to believe.
Motiv put the Venom Strike in the ball guide
http://www.motivbowling.com/resources/ball-guide.html because of it's low flare rating and weaker Atomix Solid cover compared to the Fusion and Whiplash covers which are much stronger.
In BTM they rate it with it's OOB cover 9.0, 9.5 and 9.5 for oil 5.5 torque, 12 length, 16.5 backend and 53 total hook. In OOB and with a stronger layout I'd agree where BTM put the VS is where it should be but Motiv has much stronger balls that they would rate for medium-heavy and higher.
Put a weak layout on the VS slight polish over P2000 and you have a very controllable piece for house lane conditions much like the Toxin or in that range. Dullish cover with a weak layout it will puke.
Of course this is all debatable for every bowler as our stats are different and conditions that we bowl on are different. But, this is what I see. I can understand why Motiv put it low as an early low Rg rolling piece for light-medium though OOB with strong layout BTM rates it as a for heavier.
VS with good sport layout would be a great sport lane condition ball.
IMO you have to watch out for how reviews and manufacturers rate balls and get your pro shop involved with your stats. and conditions you are trying to match up on. Take a look at how JustinWi lays out his equipment usually with three layouts for his stats.....usually two of the layouts are weak pin up and pin down and one strong.