How to identify a spell being cast? discusses how to identify a spell.
This question seeks to discover whether there are steps a spellcaster could take during casting to make this identification more difficult. The question is not about hiding the casting (such as casting the spell round a corner, then releasing it with a reaction) - the person trying to identify the spell has full view of the spellcaster casting it.
Such steps might include:
- Putting some irrelevant words around the actual mystic words of the verbal component
- Waving your hands as if performing a somatic component, despite the spell not having one
Is this sort of thing possible while casting a spell (to be clear, without any special capability such as the Sorcerer's Subtle Spell), and if so what effects does doing so have on spell identification?
Assume for the purpose of the question that the rules from Xanathar's Guide on spell identification are in use.