Road bike category introduced by British time trial governing body to "get more people time trialling"

The 90mm rule is not dissimilar to that which the UCI and national governing bodies use for road racing. It's to prevent someone getting an excessive advantage. Also, with wheel depths, what works better for one rider will not necessarily work for another.

As a tall but very light rider, I already present a large surface area to strong crosswinds, and can easily get blown sideways even on shallow rims. I would never ride anything over 60mm deep, 50 is my sweetspot, simply because fighting to stay upright makes me slower on deeper rims. 

There are TTs that don't involve dual carriageways...

Most A-road dual carriageway courses have been retired, and are now run on single carriageway A road and B road courses. Whilst it is not perfect it is much safer and thanks to a push from regional committees, the website is getting all the proper information reinstated such as couse maps etc, so organisationally it is improving. Some even run on closed circuits, although this is not very common.

I understand the feeling though. I'd be up for entering a TT on my road bike (it's either that or my hybrid!) but I don't fancy racing on open roads. I've entered a few running races (my main sport) on partially closed roads, and now generally avoid them. I'd be very unlikely to race a bike in moving traffic.

I only have experience from a couple of courses, but the ones I have raced on are relatively quiet. Event times are also taken into consideration, as most club TTs are done either on midweek evenings (7pm) or on Sunday mornings, when overall traffic is reduced. I would suggest looking at a few local courses, and speaking to club and organisers to find out what courses are generally quieter during race times.

Ah, that's interesting, I hadn't considered the timing of the races.

Still not sure about the racing on open roads though. Running races where part of the course is on a road where one lane is closed to traffic are still relatively unpleasant. But good to know about courses/timings and what's done to minimise traffic.

Although now I can see I'm complaining about riding in traffic when almost all my riding is my commute!

As per previous posts, some courses are naturally quieter and/or at quiet times of day. Plus entrants generally start 1min apart, so it is just you riding a route as fast as you can. You won't be battling to get down the side of queues of traffic, and everyone just has to deal with any roundabouts or fast corners as you would if you were riding normally and abiding by the laws of the road.

As with just about every other aspect of post-modern life in our society, cycle "sport" has been transformed into an advertising and marketing facility for the producers and sellers of cycling "goods". The sporting aspect is a just a hollowed out container in which consumer-producers compete at being able to buy "the best" stuff, winning at spending rather than cycling.

If TT and road racers want to return to true sport, all the bikes would be identical except in fit to suit various body types and sizes. Like keirin in Japan, where bikes are semi-identical to make the rider abilities the focus rather than the bicycle made advert being the point. (A result of the gamblers need to differentiate rider ability from bike tech).

This latest CTT move is likely to result in another buying spree of exotic and expensive bike parts deemed "essential" to give the edge in this new class of consumer-competitors.

"Ah", you cry, "...but this focus on equipment gives us non-competing cyclists lovely new tech and shiny things"! Yes, that's the point, innit. Bikes as a new designer-frock or the latest outrageously expensive posing-handbag.

I wonder if this really has much value. Last nights club TT saw more road bikes than TT bikes. As usual. It varies of course. I use the road bike on the hilly routes and the TT and the flatter ones. Every club TT I go to is the same. I assume this is really aimed at getting people into opens not club events but by the time peope are keen enough for that they have mostly bought a TT bike as despite the " you are only racing yourself twaddle" we are all after the best time possible and fully intend to beat our mates.  

I believe that open events are different, and that most Open entrants are often riders with TT bikes as opposed to club events. 

Even so, the option for a seperate "road bike " category makes the sport feel more accessible. By having the seperate category, you can compete and compare yourself to those with effectively equal machinery. It makes it fairer for those who either cannot afford a TT bike or are just trying out the discipline, who want to ensure they like the format before making an investment.

I can't find a single brand manufacturing an affordable alloy framed TT bike when 10 years ago there were a few on the market. Pretty much all new TT bikes are £12k plus, are electronic shifting only and full carbon.

Even secondhand bikes are keeping fairly high value due to the low mileage and high nuance/low demand for such machines. It is by far the most difficult job to do on a budget.

Id be interested to see the qualifying criteria for the races. You could theoretically stick drop handlebars on a TT frame and its a regular road bike. I think ive seen Youtube tests of a road bike with TT bars vs a TT bike with drop bars and even the most aero road bike like a Cervelo S5 is no match for a dedicated TT frame. 

There should be a max rim depth and frame dimensions to adhere to or its just another category where tech and money wins 

Interesting notion about TT frame drop bars vs aero road bike frame with TT bars. I am unsure of the exact rulings (also, the CTT does not follow the same rulebook as British Cycling and the UCI) but I do believe TT frames built as a road bike will not be allowed. Also I imagine the handling of such a machine would be very nervous and twitchy pitching your weight so far forward, especially in the drops. 

However I can confirm Maximum wheel rim depth is 90mm and clip on tri bars are also not allowed. I also believe that TT helmets are not allowed as well for the category. We won't get any ridiculousness like we did in the Tour Down Under prologue. 

Whilst the best equipment money can buy that is legal within the category would give you a small advantage, it is also not likely to be the decisive factor for a winning margin.

People's physical ability and flexibility, power output and efficiency and rider skill on any turns are likely to have a bigger affect on race outcome at amateur level.