Funakoshi Gichin, founder of Shotokan Karate, was once asked what his rank was after the implementation of the kyu/dan system and I believe his response exemplifies the mentality we all should maintain. He stated simply that his rank was of no significance, that rank was merely for the students. Rank was designed to be a tool to measure the progress of the student within a given system by the instructor. Therefore as the headmaster of that system, you technically have no rank within that system. Numerical rank is unnecessary as you automatically hold the highest position. Position and title ultimately supersede rank as it is, so to self proclaim 10th Dan is not only redundant, it's just wrong. When I say title supersedes rank, this means (and is a very exaggerated example) that a low level practitioner who is named the inheritor of a system by the previous Soke assumes all responsibilities and authority as the headmaster of that system regardless of their personal progression and rank. From that point on, it is up to those higher up in the system to aid the new Soke as advisers and get them up to par but that does not negate their actual authority to issue rank and licenses to any level. So if holding the rank of 10th Dan is unnecessary for the headmaster to fulfill the responsibilities of their position, where did the trend come from?
In Japan, there is often a system of checks and balances that prevent people from making bogus claims (not the mention the concept of dojo suburi). I'm not saying that the pioneers did not deserve the ranks they claimed, as dojo wars were prevalent and forced everyone to back up their claims, however the trend was started for self promotion and as long as you could handle yourself, it was left unchallenged and legitimate by default. But was it really legitimate? As the generations passed, dojo wars became less common and are now practically nonexistent, leaving the door open for those who could not have backed up their claims to self promote just as fast as the next person and now those who self promote are shunned and blacklisted for simply following the example of those before. Then began the concept of trading documents and ranks to further muddy the waters of legitimacy, since now the self promoters had documentation supporting their claims.
So then is the answer to go around and physically challenge everyone who wears a 10th Dan? No, of course not. Surely we're more civilized than that. In my opinion, there are only a few ways to legitimately obtain the rank of 10th Dan. If you have been named the inheritor of your respective system, more often than not along with the title of Soke your instructor will promote you to 10th Dan or give you specific time frames/requirements as to when you begin wearing that rank. If your system is governed by an international organization, such as the International Judo Federation, then you may be elevated to the rank in your lifetime or posthumously by the directors of that organization. Lastly, your students may recognize you and elevate you to the rank (provided they have the proper qualifications which I will discuss in a later article). If you are the founder of your own system, and have obtained legitimate credentials as described in my last article, then your position as headmaster should be enough as it carries with it all of the responsibilities and authorities needed to govern your new system. If you need more than that, perhaps the problem isn't the rank system.
On a related note, the title of Soke was never meant to be used for founders. Translated, it means "Head of Family." Referring back to my previous article regarding foundership, your system (and thereby your family) is not considered complete until after it has been passed on to a successor. That successor, and all subsequent headmasters, would be referred to as Soke. You as the founder are technically the Shodai Soke, however it is more proper to use the title of Kaiso which literally translates as "Founder" and "Patriarch." Honestly, the most honorable title I believe anyone can be called is Sensei, as it is a term of endearment from those who have trusted not just their martial arts instruction but often their lives to you. Meaning "One who has gone before," you are not just a teacher but a guide, a mentor, a confidant, a friend. Isn't that something we all strive for?