"A man whose whole attitude is orientated by the principle of sensation belongs to the sensation type.
"Normal sensations are proportionate, i.e. their value approximately corresponds with the intensity of the physical stimulus. Pathological sensations are disproportionate, i.e. either abnormally weak or abnormally strong: in the former case they are inhibited, in the latter exaggerated. The inhibition is the result of the predominance of another function; the exaggeration proceeds from an abnormal amalgamation with another function, e.g. a blending with a still undifferentiated feeling or thinking function. In such a case, the exaggeration of sensation ceases as soon as the function with which sensation is fused is differentiated in its own right." (Psychological Types, 587-8.)
So functions can be blended. Where do Lenore Thomson's tertiaries fit in this theory? Nowhere, because they are not needed.