I'm prepared to accept that they occasionally sell at a loss, either to shift stock that isn't selling or as a 'loss leader' - something which most retailers do.
What I do NOT believe is all this codswallop about hoping the boss isn't watching in case the presenter gets the sack, taking the price too low by mistake, getting special authorisation from management to take the price lower, and other such porkies; nor do I believe oft-repeated claims that this is the most amazing piece the presenter has ever seen. It's possible that some newbie and/or extremely gullible viewers may actually believe this tosh, and it's unethical to mislead them in this way (even if it rakes in more sales); for the rest of us, it simply damages Gems' credibility, as others have said. (Not that Gems are the only perpetrators, by a long way.) I wonder what would happen if someone complained to the ASA about these bogus claims? I suppose it would be pretty hard to prove whether an item was or was not the most amazing gemstone a presenter had ever seen, which is why they think they can get away with it.
I actually like Gems TV, buy from them and don't often knock them, but I've simply had enough of this. Please, Steve, stop it!