Zelandakh, on 2017-October-21, 02:39, said:
The important lesson I take from that regulation is that a player should absolutely NOT comply with the rules if giving an explanation. All they are doing is providing evidence against themselves if things go wrong.
Law 21B1(b) said:
The Director is to presume Mistaken Explanation rather than Mistaken Call in the absence of evidence to the contrary.
As a written evidence is stronger than a spoken evidence the absence of written questions and explanations makes it more likely that the Director will apply Law 21B1(b) and rule mistaken explanation in such cases.
So it should always be in the interest of a player asking a question or giving an explanation to do so in writing when required by regulation and/or conditions of contest.