Cost: -10%/level; maximum of three levels
Extravagant Rituals is a limitation on Magery where words and gesture are required. Doesn't effect time and energy cost.
It is the opposite of Easy Casting
T38 alterations to it when using Flexible Rituals basically make it a point crock where taking it makes higher levels of magery cheap.
There's never ANY penalty when rituals are not omitted, for one thing.
Even when they are though: an extra -2 can be compensated by +2 to magery.
At -10% per level, you could split that into an extra -1 per -5%.
-20% (-4) is the most notable since Magery's base costs are in multiples of 5 so it works out to a round point.
Taking -4 would save 1 point on Magery 0, and 2 points on extra Magery.
Once that saves enough points to buy +4 Magery is when the point crock occurs.
Partially Limited Magery is also useful to note: you could JUST limit higher levels, and ignore the penalty when only using higher levels. Something not possible with Easy Casting (ALL must be enhanced)