The Viper designs are pretty much cut down versions of Frankie Hubbard's "Edge" and Frankie is long departed, having died in 2003 at the young age of 41. The Edge, the Vipers, and the much loved Ocoee are all hard chine boats. The Viper 12 happened to be the first hard-chined whitewater canoe I owned and yes, there was definitely a learning curve.
With a hard-chined canoe you may find yourself tripping over the "edge" a few times, or more than a few times. This can easily happen if you get sideways to the current and your downstream chine hits what Wayne Dickert used to call an "unfer" or "unforseen rock". This can happen quite quickly if you are trying to enter an eddy and do not notice a barely underwater "guard rock" for example. A soft-chined boat is much more likely to slide over the rock without upsetting.
You can also trip over the edge crossing eddy lines if you don't have your heel right, or have insufficient heel. But the chines can be used something like keels by weighting a knee and allow very crisp lines on ferries, and snappy eddy turns. If you are really good you can execute a very dynamic eddy turn by dropping your downstream knee and snapping in with an offside heel, like a freestyler's post. The flatter bottom also allows for much easier flat spins, and you can control wave surfs much more easily with edge control.
In my experience, most whitewater boaters who paddle hard chine designs for a while seldom go back to soft-chine boats. The exceptions would be the hard core creekers who like to rock spin, splat, and boof off of everything. The softer chines tend to slide off rocks in a much more friendly fashion with less wear at the chines.
If you plan to use Dynel I would suggest using it externally under the pedestal or seat area and along both chines. Anything that adds thickness to the hull will add stiffness. Dynel is not as strong as S 'glass but it is pretty strong and it does hold up well to abrasion.