These guys or lesbians (because I still to this day have not met an RS female who doesn't look like a lesbian or is one) are the thickest of the thick!
Just imagine being such a loser that you fail your basic trade course at SEME or SEAE and instead of joining another corps or re-trading to another job you have the brilliant idea of becoming a military training instructor. But with this job you won't be teaching just anyone. Oh no. RS teach normal REME tradesman military skills.
Regimental Specialists are often referred to as Regimental Spastics due to their minimal schooling and in most cases being so thick they failed a basic VM course. It takes a real special person to be that thick. RSs are pretty much pond life (which could explain why one of them threw a hissy fit when somebody got into the pond at SEME); no one in the REME respects these creatures. Often found lurking in the tech stores when not doing their job.
In addition to those described above (which, in truth makes up maybe 2% of the REME RS population), there are also several ex-infantry who transferred to take advantage of pay/promotion within a Corp as opposed to that available to them in their original regiments. I did my SMC with 5 of them, all ex-inf full screws who wished to transfer. They are highly knowledgable, skilled, experienced individuals who occupy a necessary role within the Corp, pass on their knowledge and tips during the training days for the Corp (Soldiers and Tradesmen, remember?) and do so to the very best of their ability. I can honestly say that in 14 years I never once heard an RS (or RD as they were previously known) referred to as a Regimental Spastic. Never met one who was failed VM either, come to think of it.