Hi Graham, I did loft and cut the CS-17 in one day, though you're correct, I didn't have the scarfs (I used Payson butt joints) completed in the same day. The following day I performed the butt joints, doing them all at once in a few stacks (both sides). Admittedly, I'm likely a bit faster then the average Joe, building a Core Sound (not my first rodeo), but a little forethought (another skill often not seen in home builds) and planning could achieve these results.
I have no doubt (never have seen a kit for this) she'd assemble quicker and more accurately for many home builders. I think the most important thing mentioned that Graham has offered, is the confidence a tentative builder can gain with a kit. I can see this not only being a solid "tipping point" for a prospective builder, but a huge boost in confidence, when "tab A" fits precisely into "slot A". There's enough head scratching and crying in any build, so a kit can ease a fair bit of this and it's a consideration that can't be as easily "qualified".
Maybe I should qualify my above comments in that, from the beginning of the build, several "changes" where planned, necessitating a loft. For example, the transom has twice the rake, of the one shown on the plans. A kit for me would have been more effort, cutting in "Dutchman's" every place I made a change. Another example is the cockpit seats followed a curve, mimicking the sheer in plan view. Yet another example was the curved transom, which means one supplied in the kit wouldn't fit. The list goes on, so for me and I'll bet most skilled builders, the time savings wouldn't be as significant, but (and it's a big but, much like my other half's, whom I hope doesn't see this) the person looking for speed, accuracy and perhaps the security of knowing how well the parts fit - well the kit is a hands down deal maker and this portion of the industry has revolutionized home builds, with likely much more to come. Now all we need a is a 3D printer, that can pop out wood fiber and resin hull shells - so when are you getting one of these Graham?
Below you can see some of the changes on the build. The noted curved seat boxes can be seen, but also the enclosed centerboard case (no arm), no aft bulkhead, which is replaced with a removable seat and a substantial athwart brace on the transom, the curved combing, the side decks shapes are different - in fact a bunch of changes (yeah, those lightening holes aren't on the plans either).