Ok i've searched around the internet on the actual benefits of investing attrib points into beastmaster and here is what one person had to say.
"A pet can be very powerfull, with no points invested in beast at all. As a matter of fact beast will probably end up giving you a less powerfull pet then if you boosted wilderness for instance since you can get healing spring, which will heal both your pet, and any other party members/allies and minions you have.
Pets can be usefull in pvp as well. The most usefull ability a pet has is disrupting lunge by far. This will destroy a spellcaster big time. Disrupting lunge, and beast again needs no points to be effective. And since most players don't bother to target a pet anyway, this makes them even more effective."
Personally i think he's full of it because they should pretty much take the beastmaster skill out of the game if it were true. Furthermore he goes on saying that increased points in beastmaster skill just increases your pet's chance to do a critical hit but not how much damage he does. So a level 10 beastmaster will kill an enemy 10 percent faster than a level 0 beastmaster. LOL Please tell me this guy is smoking the ganga.
If any of you rangers here have some light to shed on the subject i'm all ears.