Do you want to use Alteration? Take these. Take all of them. Take them so damn hard.
Alteration Dual Casting-
By doubling the duration of Alteration spells you can accomplish... not much, actually. Since this only affects the ‘-flesh’ spells and the Paralysis spells, it’s unlikely to be of much use until the late game, unless you get in a lot of fights that last multiple minutes (tip- if your fights last that long, you’re taking a serious risk and need to reevaluate how you’re fighting) or keep your ‘-flesh’ spells up constantly out of a sense of paranoia. Even later on with the Paralysis spells, you probably want the spell in one hand and a weapon or offensive spell in the other so that you can actually quickly do something while your enemy is inactive. Dual-casting Paralysis isn’t all that useful- while it’s a nice long period of inactivity, the base 15 seconds is plenty to murder the kidneys clean out of virtually anything that you can expect the spell to actually work on.
This perk drastically increases the value of the ‘-flesh’ spells... but only if you wear no armor of any sort while the spell is on you. Invaluable to those who insist on wearing robes, it’s unlikely that you’re going to stay in robes should you develop any significant Enchanting skill and thus the perk is rendered mostly moot. Should you be fine with wearing no armor (which does at least save you a lot of carrying weight) this perk, particularly at full power with three perk points invested in it, will save your berobed behind probably more often than you really care to think about.