Ah, I'm not assuming anyone to be argumentative. I just misunderstood it as referring to a sword model, rather than a gap.
As for the gaps, well, that's the years they came up with new patterns. The British were all about standardization, and once some weapon was standardized, they kept producing and issuing that pattern for at least a decade, usually more. Though as I was saying, for officers it was allowed to buy your own sword after 1827, as long as the hilt looked standard from the outside. (INSIDE the handle a lot went for the full-width tang of the "patent hilt", but as long as you couldn't tell from the outside that it's a different hilt, all was well.) Non-officers still got the standardized swords, though.
Sort of how the US army was still issuing M1911A1 pistols in '86, after they standardized on that model in '24. It's not as much a gap, as just the old standard was still being issued.
As for the nomenclature, well, that was obviously for the British army, since that was the cap'n's objection. Other countries obviously had their own names for them.