我认为“鉴定”是鉴别并且确定的意思。也就是分析辨别并确定下来。它一般用在比较严肃正式的场合。 “完毕”是完成的意思，一般是向人汇报某动作或者任务完成后所用的词，包含果断的意味。像英文的over。 网络上说“鉴定完毕”带有幽默的意思。比如一个人和另一个人开玩笑说：“你真是一个疯子，鉴定完毕” 英文可能是”you are crazy,over" 希望帮到你。

It means identify finish. Usually, it follows with some words which is negative.

when some personal appraisal is made as a comment in bbs, to make it assertive or sometimes playful, we use 鉴定完毕，as an ending. literally,鉴定完毕 means "assessment done"

鉴定完毕=over. over

it means I got all the information afterward