If you have a multi chine hull, it is just easier to glass the whole exterior. Too much feathering otherwise. for not enough weight saving. The same goes for a multi chine deck.
I was going to say this as well. On a multi-chined hull the various pieces of tape will end up being very close to each other or even overlap each other.
I've a firm believer in skinning both sides of my S&G kayaks in fiberglass cloth rather than just taping the seams. It's not for strength or added abrasion, it's the time and material saved by not having to feather any taped joints. Sanding sucks. Why make extra work for yourself...
Skinning both sides of the plywood doesn't add much weight either. The last S&G kayak I built was my wife's new Atka-16 baidarka (16.7 ft LOA x 20.5" wide). I used 3mm okoume and skinned both sides with 4oz cloth. The bare kayak prior to outfitting (deck clear coated and hull painted) weighed only 30 lbs. The outfitting (hatches, seat, footbraces and rudder) added an extra 7 lbs: 37 lbs overall.