连词 the minute (that), the instant (that), the moment (that)都有“一 ...... 就”的意思，均可与 as soon as 互换使用，在口语中尤其如此，其中的 that 常被省略。例如： I'll tell him the minute he gets here. 他一到这儿我就告诉他。/ The minute I saw you I knew you were angry with me. 一看到你，我就知道你在生我的气。（摘自《薄冰英语惯用法词典》）

    很多词典都把 the minute (that), the instant (that), the moment (that) 作为单独的词条收录，其中的that可以省略，但是不用when替换。

The minute, the moment, the instant后面用that或省略that,一般是一...就...的意思。但并不是说这三个词引导定语从句不能用when。一般用when的时候就没有"一...就..."的意思了，只是强调这一特殊时刻而已。请看下面的例句：

The Moment When Everything Changes（文章题目）
that moment when you can't feel your cell phone in your pocket.
The moment when you first wake up in the morning is the most wonderful of the twenty-four hours.
The Instant When Everything is Perfect （书名）
 At the instant when the radius of the oil slick is 100 centimeters and the height is 0.5 centimeter, the radius is increasing at the rate of 2.5 centimeters per minute.（一道数学题）

The Minute When Your Life Stops （英国BBC的广播节目名称）
I like the minute when I can get off the stage and go home.

同意曹老师观点!

(1)当作关系代词使用是that正式用法

(2)当作可以省略的关系副词使用是that非正式用法，that这种非正式用法经常被用来代替定语从句中的关系副词when,where,why,包括方式状语中in which，那也为什么先行词the way为会出现以下3中结构的原因。

(1)the way sb do sth

(2)the way(that)sb do sth

(3)the way in which sb do sth

第1种是第2种省略that 形式。