Are Deep Dive and/or Wreck Dive specialties necessary?

[Jafo19D]

Let's see if I can clarify it for you since you aren't grasping what should be a simple concept

Having a bad day? Wife leave you or something?

 

[AnnikaPersson]

so if someone arrives to do a straight forward 30m wreck dive and they showed you a bunch of cards eg Adv tirimix OC Mod 3 ccr, full cave and adv wreck you'd want to do a check out dive first?

Well, it depends..
It the dive is for ex in a total different environment, with 2 C degrees for ex, and the diver has not been in this environment before or recently, I would suggest it is good to do a bit of test dive first.