Is corrective surgery a very successful solution for a cleft lip and palate?

Yes: These days surgery and specialists who are very good at surgical repair.

Absolutely!: Having seen an occasional child who didn't have their cleft lip/palate repaired eve the worst repair is better than no repair. Speech and nutrition are usually much improved after palate repair even if the repair isn't 100% successful. I don't think too many children don't get a lip repair even in third world countries thanks to all the worldwide volunteer efforts.

Absolutely: It is the only way to fix the defect. Results vary based upon the severity of the defect and the experience of the surgeon.