Pinktaco said:
If you have other rippers on the board I assume the chief's ripper will benefit from the regular's toad.
=> Why?
To me, this is another clear case of wishful thinking by those who hold that opinion.*
The rule that grants the Awesomesauce is "Toad Rage." This rule is not a rule for a generic beast calle the Ripperdactyl. This is a Special Rule in the "Ripperdactyl Rider" entry in the bestiary on p.43 (English edition) and is likewise referenced on p.93 in the Army List entry for Ripperdactyl Riders.
That's where the rule and that's the unit that benefits from it.
A Chief gets his ripper as an option in his unit entry. Within the Heroes section of the Army List section of the book, on p.87, there is a list of character mounts. This list includes an entry for "Ripperdactyl."
In this same section, in addition to the profile (which includes the Troop Type, which is why we get a Stomp for our Ripperdactyl-mounted Chief), we see a list of the Special Rules that apply to a Ripperdactyl (as opposed to a different unit type called "Ripperdactyl Riders), and this section does not include the Special Rule Toad Rage.
To summarize:
Toad Rage is a Special Rule granted exclusively to the unit type "Ripperdactly Riders" and
not to a basic Ripperdactyl. If you claim Toad Rage for your Chief's Ripperdactyl, you have given that unit a rule it, as demonstrated, does not have.
I should also mention that for every argument that it was "clearly" left out, one could make a compelling argument that perhaps it was left out on purpose as some sort of acknowledgement that a Chief is a cut above a normal skink and has trained his special Ripper to exhibit some level of self-control. Fluff goes whichever way we want it to, but the rules are what they are.
* Note that like PF and some others, I fully believe that if GW ever does issue any information on the topic, it will work out to be in the favor of Lizardmen players. I'm not talking about future state, though, only what is in the book for all to read today.