Of course, it's been proven that a couple can cruise pretty well on a small boat without an engine. Lin and Larry Pardey being the obvious example but over the years we've come across a lot of cruisers who have successfully cruised boats without engines. I won't get into it but Jay FitzGerald makes a great case for the engineless sailboat in his book Sea-Steading and it's well worth the read.
Tad's lug schooner has an outboard in a well. Tad did not mention what size motor to me but I suspect it's either a 6, 8, or 10HP (at the moment we're more than happy with a 6HP on our CAL 34). It's a simple and afforadble solution to the auxilliary power problem and has a lot of advantages over an inboard diesel engine. It's lighter than an inboard, less expensive than an inboard, less prone to problems than an inboard, and in the event that you do have a major problem a lot cheaper to fix/replace than an inboard.
What's not to love?
Well, outboards do have some issues...
For one, deploying an outboard on a sailboat is always a
Secondly, outboards are not as efficient as an inboard diesel which becomes severely problematic if you want a motor boat with sails and are one of those folk who tends to turn on the motor when the wind lessens a touch or simply can't be bothered to take your sail covers off. For sure outboards don't make sense if you want to make long passages under power. I might also add that if you really want to make long passages under power that sailboats don't really make that much sense either.
Lastly, outboards use gas and most of us don't like carrying a lot of it around and stowing the stuff safely can be a hassle but, I expect that Tad will have some super cunning storage plan for stowage of a couple of outboard tanks (and maybe a jerry can as well). Of course, being a sailboat you won't be needing silly amounts of fuel because you're going to be making passages under, dare we say it... sail.
So far we have an inexpensive but powerful rig and a capable affordable auxiliary propulsion system... Find out what else is on offer next time.