I'd guess very few as the standard technique is to extend and extend the difficult ones for many years without ever reaching a conclusion. This gives the added advantage of allowing any star ranks to retire and perhaps wear-down the complainant so they give-up or leave.
From the statistics this technique appears to work well from the Service perspective as nobody is held accountable for a case that has not been decided upon for several years.
In the civvy MoD it is even more simple. If a junior raises a complaint or grievance against a senior, be it Service or Civilian, the latter is permitted to judge his own case. End of.
If the complainant decides to pursue it higher, the delaying tactic you mention kicks in until the "offender" moves post, which should be no more than 2 years under current rules. This act of moving post is deemed to close the case.
Would be interesting to know what percentage of the current SCC's cases have found in favour of the individual rather than the Services
Good question. Just last month I visited an old retired colleague, ex-RAF and then MoD civvy, who is the only person I know who has won a case against named senior officers (as opposed to MoD in general). The Cabinet Secretary of the day (when the postholder was also head of the Civil Service) awarded him a 75% pension for life as compensation for bullying and harassment. This was a notable ruling because his successors and Ministers have ruled this is no longer an offence in MoD, which is one way of stopping such complaints.