求教，为什么相同的action对先调用的节点无效？？

Creator 2.x
#1

在做一个demo,代码如下：
`onLoad ( ) {
this.heroConfig = gameConfig.heroConfig

    this.canvas = cc.find( 'Canvas' )
    this.heroPicNode = this.node.getChildByName( 'heroPic' )
    this.heroShadowNode = this.node.getChildByName( 'heroShadow' )
    this.canvas.on( 'touchstart', this.shoot, this )
},

shoot( ){
    let jumpTime = this.heroConfig.speedJump/this.heroConfig.gravity
    let enlarge = 1 + this.heroConfig.speedJump*this.heroConfig.speedToScale
    let narrow = 1/enlarge
    let deltY = 2*jumpTime*this.heroConfig.speedGo
    let goAction = cc.moveBy( 2*jumpTime, 0, deltY )
    let jumpAction = cc.scaleTo( jumpTime, enlarge, enlarge )
    let narrowAction = cc.scaleTo( jumpTime, narrow, narrow )
    let fallAction = cc.scaleTo( jumpTime, 1, 1 )
    this.heroShadowNode.runAction( cc.spawn(goAction, cc.sequence( narrowAction , fallAction )  ) )
    this.heroPicNode.runAction( cc.spawn(goAction, cc.sequence( jumpAction, fallAction )  ) )
},`

这里为什么定义goAction，之后heroPicNode调用runAction发现heroShadowNode只能放大缩小不能向前移动，将
this.heroPicNode.runAction( cc.spawn(goAction, cc.sequence( jumpAction, fallAction ) ) )改为this.heroPicNode.runAction( cc.spawn(cc.moveBy( 2*jumpTime, 0, deltY ), cc.sequence( jumpAction, fallAction ) ) )之后正常了，这是怎么回事？
如果两个节点运动方式相同，使用定义的同一个action很正常啊，这里是因为heroShadowNode调用runAction后goAction修改了goAction对象吗？文档里有：你不应该修改 runAction 后的动作，将无法发挥作用，如果想进行修改，请在定义 action 时加入。是这个原因吗