quote：so that和so as to的区别
i don't think that gmac will ask you to distinguish between them. (if you see a split like that in a problem, then scour the choices for other differences.)
nevertheless, i think i can give you some sort of explanation: in general, you don't use so ADJ as to VERB unless the VERB describes some sort of state/condition. i.e., if the verb is an action verb, this construction generally isn't used.
for instance,
i am so ugly as to be viscerally repulsive to women. --> this works, because the verb “to be” describes a state/condition.
i am so ugly as to repel women on sight. --> you generally wouldn't see this in good writing, as “repel” is an action verb; the sentence would probably be written as i am so ugly that i repel women on sight.
so as to +
表示状态的动词在prep出现过，作为正确答案：
174. Oftenmajor economic shifts are so gradual as to be indistinguishable at firstfrom ordinary fluctuations in the financial markets.但是so as to+working verb从未出现为正确答案
-- by 会员 DUKB24 (2012/10/2 23:21:37)
REP08 174 题解释中提到：“so that可用作多个主语”，而“so as to 一般用于单一主语”。单对这道题，我觉得两个选项实在很难取舍，而OG对C的解释干脆是so as to 不是正确的idiom。彻底崩溃啊，求解救！