It is easy to train pit bulls while puppies. The real key to success in training pitbull puppies is to start the training while they are very young. The longer you delay, the harder the process becomes.
Yes pit bulls are smart dogs and the mental stimulation of training is good for them. Don't try to over train at one time. Train for 5-10 minutes then play for 5-10 minutes then train again or they will become bored and not listen.
it has been my experience that pits are a very smart, high energy, high maintainence breed. they are very trainable but in situations with multiple dogs, a pit will almost always be the dominant dog and will use agression to attain that position. that's especially true in same sex situations. you're looking at a patriarc or matriarc position that's part of all breeds, but is a very strong characturistic with staffordshire terriers and american pit bulls personalities i've been doing rescue and foster work for almost forty years and have had opportunities to work with several. one i had for eleven months to nurse him back to health and to socialize him. they can make great pets and be great with people. just know your dog, and remember always spay or neuter.