«التَّشَهُّدُ لَيْسَ بِرُكْنٍ فِي الصَّلَاةِ»
Within the Hanafi analysis, tashahhud is not treated as an integral pillar of the prayer.
The example arises because a construction using aw can refer alternatively to sitting or to reciting tashahhud. It does not automatically establish both as pillars merely by mentioning them.
This must not be misread as saying tashahhud is religiously inconsequential. The distinction between a pillar and another binding requirement belongs to the law of prayer and is not settled by the particle alone.