Dance is a limitation for Magery found on B67.
Viewing it in respect to Thaumatology shows some relations to other modifiers
- T24 Extravagant Rituals partly reproduces "not freed from rituals requiring movement as your spell level increases"
- eg "No matter how skilled you are, you can never cast a spell without at least speaking a word and making a small gesture."
- T28 Easy Casting partly reproduces "need not speak at all to cast your spells"
- MS28 No Incantations perk can buy that on a per-spell basis.
T37 mentions under Flexible Rituals "By default, all spells require subtle foot motions (like dance steps)" though there is no Dancing skill roll mentioned. It would make sense to use that as a Synergy Skill per Social Engineering.
T38 mentions alterations: Extravagant only increases omission penalties, it doesn't act as a hard cap on omissions. Easy Casting is now a penalty-mitigator.
Perks[]
Using Flexible Rituals:
- This probably functions like having the No Incantation perk on all spells
Normally this removes a hard requirement. When it's a soft requirement (you do it to avoid penalties) NI presumably just nullifies penalties.
It takes 2 levels of Easy Casting to remove the potential -4 for no incantation.
The same is true of no gestures (the max -8 penalty means there's no reason to take more than 4 levels, at +160%)
Both perks together basically include Easy Casting 4 (One Spell Only) which should be worth +32%. PLUS additional benefits of being able to concentrate better when not omitting.
Since you already have incentive not to omit (avoid penalty) that could be "take the penalty but don't omit".