At several points during the day of this removal, I caught myself saying. "Yup, looks close enough." I've reached a junction in my career where I've done lots of technical pruning and rigging over small drop zones or with valuable items underneath. A few times when I've said "close enough," my plan hasn't been. It only takes one limb carelessly dropped or one piece of wood caught by hand to break a plate glass window, crack a flagstone patio or to inflict a nagging injury on my own body. The stakes are fairly high in arboriculture, and one "close enough" moment will effectively result in a wash on the day's work. It can cost twice the price of a job to fly by the seat of your pants!
I'd like to think it's a kind of wisdom that led me, in the case of the Cottonwood above, to question myself every time I said aloud "seems ok" in the canopy. For me (and for the homeowner) it was definitely worth taking even an extra half hour to set rigging to avoid breaking things on the property or people in the work zone.
There's a reason we carry liability insurance - miscalculations do happen - but an Arborist never wants to have to use that safety net.