[Question] doesn't add up

[Saikyokami]

The following techniques are from the roleplay and so are their ranks U_U

(Suiton: Dekishi Mizu Burobu no Jutsu) - Water Release: Drowning Water Blob Technique
Rank: B
Type: Offensive
Range: Short
Chakra cost: 20
Damage points: 40
Description: After liquefying a portion of their body, the user manipulates the resulting water to surround their target's head, preventing them from breathing in order to either: render the victim unconscious or ultimately kill them, if the suffocation is sustained.
Note: Can only be used by members of the Hozuki clan.

(Suiton: Mizu Shibo no Jutsu) - Water Release: Water Entrapment Technique
Rank: B
Type: Offensive, Supplementary
Range: Short
Chakra cost: 20
Damage points: N/A
Description: Through the use of the Hydrification technique, the user releases water from his hand towards the target that then binds them in a prison of water and restricting their movements.
Note: Can only be used by a member of the Hozuki clan.

Both mentioning the use of the Hydrification technique U_U

(Suiton: Suika no Jutsu) – Water Release: Hydrification technique
Rank: A
Type: Supplementary
Range: Short
Chakra cost: 20
Damage points: N/A
Description: This technique allows the user to liquefy the whole body at will, this technique makes it impossible to receive damage from physical attacks. From a single hair to the skin and muscles, everything can be liquefied and solidified at will. Be it to evade an enemy's attack during a short range battle, to infiltrate a structure, or to launch a surprise attack in a liquefied state, this technique boasts a high strategic value. Using this, the user can also re-shape their body parts for suitable situations. The only way to contain a user of this technique is to lock them up in an airtight container so they cannot move about. When the user passes out, they turn into a jelly-like state. As this technique turns the body into water, the user is vulnerable to lightning techniques. The Second Mizukage when using this technique has a more oily state allowing it to into Gaara's sand element and nullify the techniques. (this oily ability can only be used by the Second Mizukage).
Note: Can only be used by members of the Hozuki Clan.

But you don't learn Hydrification technique until A-rank but the other two are B-rank.. How does that work?

 

[Nathan]

I guess the person will teach you the A-rank first then go back to the other techs.

 

[Caliburn]

These are Houzuku clan techs, it's not weird in such situations that you first need to learn a higher ranked jutsu to be able to use some lower ranked jutsu's. Those B-ranked jutsu's are on itself not really that powerful, it's just that you require to know a higher ranked jutsu before you can use them. First you just learn the A-rank jutsu as that one is required to pretty much learn all the other Houzuki jutsu's.