The term "splinter skills" actually can be applied to anyone (not just autistics) with one or two skills that are considerably above their overall performance ability.
People with learning disabilities usually have average or higher intelligence, with difficulty with acquiring print skills, memory retrieval, and/or with perceiving the patterns in math. If they also have a skill that is significantly above their overall functioning (in areas other than in their learning disability area), then that is considered a splinter skill. For instance, they may have extreme difficulty with reading and writing (their LD area), perform with average skills in fine arts (their "expected" performance level based on their overall intelligence), and be amazing when it comes to math and scientific inquiry (their splinter skill)...a profile of LD people often found in engineering careers. Splinter skills is a term used with autistic individuals. Splinter skills usually refer to talents and unique competence by a person that is disproportional to how that person functions is other areas of their life. With an autistic individual, being able to play the piano really well or memorizing long passages would be considered a splinter skill because the person is having difficult doing the everyday things expected for someone their age.
Children with other disabilities like Sensory Integrative Problem may also have splinter skills.
An example of a "splinter skill" is the ability to play a particular song on the piano without having the general ability to play the piano.
It could also be that they have an unusual memory for numbers (think Dustin Hoffman in Rain Man); exceptional ability to read, write, spell. They could be extraordinarily good with ); art; music; mechanical or spatial skill; calendar calculation; mathematical calculation; sensory sensitivity; athletic performance; and computer ability. These skills may be remarkable in contrast to the disability of autism, or may be in fact prodigious when viewed in relation to the non-disabled person. Source(s):