Agreed Old (as in 30 years old plus acoustics) require a neck reset in most cases, because of the stress they have been under by 12-13 gauge strings over such long period. And these acoustics usually have pretty bulky necks. Electrics on the other hand tend to not be stringed with that heavy strings and thus, may not require such process. But on the other hand, many have skinny weak necks on them (SGs, Ibanez style instruments). In the event that they do twist however, it will most likely depend on the type of stress they were under and the strength of the particular piece of wood that is the neck. This strength may not symmetrical. How much of a twist though? My belief is that if the neck is sterdy enough to begin with; the possible twist will not pose a problem and will be dealt with so little as a simple fret level. A weak neck, like an early Ibanez Wizard neck which was extremely thin, single piece maple, will likely have more trouble. There are also many other reason for a neck to twist, completely unrelated to string tension. Personally, I became kinda supersticious and switched to regular sets, after having used hybrid sets for a few years.