A typical question is "Why should I become board certified". Of course there is no regulatory office in any country which regulates which procedures are exactly to be performed by which doctors. In most countries it comes down to "you perform whatever you are proficient for".
Even within the diverse specialities the training gets more and more specialised into subgroups of knowledge and expertise.
An independent certification guarantees I minimum degree of proficiency. In some countries this could be recognised as its' own speciality by the doctors associations; in most countries it will remain an unofficial status. Nevertheless doctors should be encouraged to undergo the extra training and get certified. It will be appreciated by the patients.