Erasing, whiting out, or removing an entry in a legal document like a log (flight, maritime, medical, etc) so the original entry is no longer legible is against all standards for such documents. It raises questions about what was originally there, and why it was changed, and seriously jeopardizes the document's legal credibility. In some cases, such as medical records, it can be a crime (even a felony, in some jurisdictions) to do so. The only acceptable way to alter legal records like your logbook is to line through the erroneous entry (leaving it legible), put the correct data above it, and initial and date the change -- and be prepared to explain why you made the improper entry in the first place if it ever goes to a legal proceeding.
As for FAA enforcement actions, this one's been tested -- it is not considered "self-incrimination" if your logbook provides the evidence to hang you. You can "take the Fifth" as regards any explanation of the entries, but they can use those entries against you, and the ALJ can decide what they mean with or without your assistance, and you cannot refuse to provide your logbook for examination on those grounds. As for having your logbook mysteriously disappear, ask Richard Nixon what happens next.
IOW, once you put it in your logbook, it's there -- it's done -- it's written for all time. If you find you entered evidence of wrong-doing by mistake, you can correct it as described above. Otherwise, you're treading on the edge of criminal conduct if you alter your log to conceal evidence of wrong-doing. Consider this good reason to think carefully about every mark, letter, number, and comment you put in that official legal document known as your pilot logbook, and not to enter anything you don't want held up in a legal proceeding later, be it an FAA enforcement hearing, a civil trial for negligence/liability, or a criminal felony case. As we used to say in the Navy, "TINS" (This Is No Fooling, or something like that).
