Cynewulf, what you are suggesting would literally make Mystic Adepts (and Aspected Magicians) completely pointless.
It's a case of specific trumps general. Adepts have access to magic-related skills (in general), but another rule states that skills from the Sorcery, Conjuring, and Enchanting groups are still off-limits.
Also Assensing still specifies you must be able to Astrally perceive to get it, that doesn't go away either.