(As for hardness, it's probably personality-dependent. The Norfolk 600 that TG took us on in 2008(?) was by far my easiest, and some people do loops from home and love the independence/solitude. But there is probably a really easy calendar 600 that I haven't done yet - possibly also rather dull!)
I designed that route to be easy because it was for helping someone ride their first 600.
We only have calendar 600s in the summer. If you like, we can ride the Norfolk 600 in January. It'll be interesting to see how much it moves up the rankings as a tough 600.
The Seething 600 should be similar. Probably easier in fact because it's probably not 40km over distance like our DIY was.
Forgive my niavitay, but I do wonder how often more than 4 calendar 600s have been ridden in a season.
frankly frankie will be along in a minute but ASTR that in the '90s Robert Fry and one or two others rode 5 x 600 or 6 x 600 on successive weekends.
Seven riders gained their Super-Randonneur by riding four 600s, with Graham Moult and Robert Fry riding six on consecutive weekends.
I think Jack Eason has ridden more than 4 calendar 600s on consecutive weekends. Once you start riding several calendar 600s a year you end up having to travel a long way to and from events. It's not like we have several 600k calendar events all over the country every weekend. With DIYs, it's probably less likely for people to do more of the longer calendar rides, unless they are classics like Bryan Chapman or Daylight. Riding a 600 is time consuming enough for most without adding on extra travelling time and expense.
Or is it that the same number of people are riding as many 600k calendar events as they would do. But in addition to that, they can now ride some extra 600k events because they can fit it in. Whereas before when they'd have to have travelled to and from an event or an event was on a day that they had to do something else, they can ride it when they can?
Not all DIYs are equal though; group DIYs are, more often than not, much 'easier' than solo DIYs. Having company/contact makes a huge difference, even if sporadic and just at controls such as riding the majority of a calendar 600 on your own.
Not all 600s are equal. Not even the same calendar event is the same ride every year.
Riding with company? It's only helpfull if you ride with good company.
Some people need company more than others. I'm often happy with just my radio for company.