Bolt-on

Some guitars have the neck glued to the body (Les Pauls), some are bolted on (Fenders), and in some the neck is part of one piece of wood that extends through the body (Jackson). The theory of the neck through the body design is that if the pickups, bridge, and the strings (from tuners to tailpiece) are mounted on the same piece of wood, sustain will be greatly enhanced. In practice, a well joined glue-on and a properly fitted bolt-on will sustain just as well.

I would draw a distinction between transplants and cross-fertilisation. […] Cross-fertilisation implies a different, more indirect process. It implies that an external stimulus promotes an evolution within the receiving legal system. The evolution involves an internal adaptation by the receiving legal system in its own way. The new development is a distinctive but organic product of that system rather than a bolt-on.

Should not a curriculum for the twenty-first century be organised more effectively around the new technology? At present, it remains an addition to most subjects – a bolt-on.

Friday night's crowning victory at The Hawthorns was the 25th in 30 league matches since Antonio Conte's decisive re-gearing of his team in September, the tactical switches that have coaxed such a thrilling run from this team of bolt-ons and upcycled squad players, most notably Victor Moses, who was dredged out of the laundry bin in the autumn to become a key part of the title surge.

[I]f an innovation has reached the maturity stage of the product life-cycle, then perhaps its functionality will be developed to provide a ‘bolt-on’, with the core of the innovation remaining essentially the same. A classic example of a sustained innovation is the mobile phone, where functionality is increased by adding on extra capabilities, such as video, Internet acss, GPS tracking systems, music, and email.

PureGym (puregym.com), which has more than 200 gyms across Britain, charges from £8.99 to £17.99 a month, with "bolt ons" available.

[T]he first model of this now most famous line of related types, the [Gibson] Les Paul also appeared in 1952, […] The trapeze style tailpiece and combined bar bridge was also fitted, although this gave way to a bolt-on bar bridge by 1953.

Marketing is not an option, a bolt-on activity, or for moments when 'time allows'; it must be present all the time as the company goes about its business.