Is "parboiling" chicken stupid (or wasteful)? I realize the question can be considered inflammatory - use the latter wording (wasteful) if it helps...

When I learned (taught myself) to cook and first figured out that meat does indeed have a flavor of its own, I struggled and finally learned how to retain those flavors - everything from making broth with bones to slow-cooking to release natural fats and connective tissues. However, a friend uses chicken that is "parboiled" in many dishes, and this seems quite wasteful to me.

I understand that parboiling can be done to reduce cooking time. However, help me either understand this preparation mentality, or explain to them how to do things better...

My friend puts chicken breasts into a ~3-6 qt saucepan on the stove in warm water, turning the burner to high. After the water is boiling, heat is reduced to medium (50%), and left to boil for 30 minutes or so. The pot is drained and the chicken either shredded or cubed for use in a pulled-chicken or similar dish (perhaps enchiladas or similar). The chicken is fully cooked, but usually lacks taste - as I figure, it was all boiled out of the chicken during cooking.

This seems wasteful (stupid) to me - as the friend often goes through extra effort to use high quality ingredients, spices, seasonings, fresh herbs, and selects healthier meals. The only potential gain I see to preparing the chicken in this fashion is that the cooking can be done relatively unsupervised (plop chicken in, adjust heat once, and walk away). However, taste is lost when instead there certainly must be a better way to prepare the chicken. Perhaps in the case of the aforementioned enchiladas, the chicken could be placed in a skillet, half-covered with a mix of enchilada sauce and water, covered and cooked on medium for just about the same amount of time. This would flavor the chicken more instead of removing the flavor, and with little additional touch-time.

This friend comes from a background of much prepared food and poor cooking habits growing up, but has taken the time to advance their skills greatly in other culinary areas aside from meat preparation. I'd like to encourage them with evidence (and gentle pressure if necessary) to improve this facet of their cooking as well. Perhaps they are used to canned chicken which is precooked, as I believe this method for cooking chicken originated out of one snack-dip-related dish, which was a staple for them previously.

Bonus points: is this technique even parboiling? Above-quoted answers cite parboiling to be boiling to speed-up preparation of the parboiled food, but don't mention the intention of completely cooking it.
Chicken breast is so lean and bland already that I'm not sure this method would really be that much worse than a different method especially when being shredded and mixed with strong flavors.

I don't think it's wasteful unless it is not eaten, but a far better way would be slow cooked and then shredded thigh meat. It is fattier, but in my opinion, a far more delicious part of the bird. It is stronger flavor wise, has an unctuous that chicken breast can't touch, and is cheaper.

Back on topic, if you really wanted to prove the value in either grilling or slow cooking the chicken breast. Do two batches next time: one half is yours and one half is theirs. You should definitely marinade yours if you want to win :)