Some people claim Perceiving Magic works against sustained magic. I personally disagree. However, every spell is visible on the astral. A quickened spell simply no longer requires sustaining, it still is a spell, it still is a magical boost, it still can be taken out by wards and it still is visible on the astral as it has an aura. If you walk around with five quickened spells, any assenser will see you have 5 auras with you and will realize you're likely heavily possessed or prepared for war, so will call for HTR. HTR will kill you if you don't surrender, knock you out if you surrender, then throw you through weak mana barriers until all spells are broken, and THEN they'll wake you up, in magecuffs, and interrogate you.