But Slinky can't harm TT, and the restraining willnot be as effective. Plus, TT scales somewhat to The Scorpion, who has avoided being entangled by a snake, like Slinky would. TT is also more athletic, acrobatic, and has fighting skill and exp, which Slinky only has part of. Plus TT has better range via various web attacks, and can retreat if need be.
I mean, Slink is Woody's deputy, if you will, and has shown himself to be a pretty capable and loyal dog. For a particular instance, he found Woody's hat with Buster when he lost it at the beginning of Toy Story 2.
So, I agree that he likely won't fall for any simple traps the Tarantula could set.