Ugh...we'd yell at you guys around here.

To echo above - yes most of the racers here open up their brakes (rim brakes) before racing. most of the big name wheels are so flexy that they will touch the pads when they get out of the saddle accelerate out of corners. Kind of why our wheels became as popular as they were in heavy crit racing scenes.

Touching brakes or braking in general usually gets people yelled at around here. You don't move around a pack with your brakes. You do it through controlling speed. If you're not actively moving up then you're moving back. No brakes needed to do that.

Yes technical corners do require braking and good brakes are nice.... but I can still line up fields of racers who lament the pileups disc brakes cause (the riders cause it but it's too much power for braking in crits).

To go fast you need good brakes....yes absolutely. In cross, road racing, mtb, enduro, downhill..... Crits not so much. In the same kind of way you don't need them on the track: you have technics to change your relative speed well and don't use your brakes because that's too bike of an abrupt change in speed.

I know most of you on here have raced crits and or continue to. I guess it just shows how different the race scene is depending on your area and terrain. Chicagoland is "Critlandia". So much so that as USA Cycling's Local Association President I have had to step in and use association money to make a single road race happen at least once a year. We don't have the terrain, or welcoming municipalities to allow for racing over township, village, city or county lines. As such we have piles of intensely fast technical flat crits. Brakes are only needed in certain situations and are often overused by lower category racers.

As for the shifting... Sure. You can do well in a couple of gears. Yes I have watched racers with downtube shifters do well in most of a race. You're dead in the water for a sprint...or you're starting it over geared but you do you. To this day if you're 50+ feet off a corner you can hear all the shifting happening every single lap. You can use the sounds as a guide to tell you how hard they're going or if anyone is attacking, etc. I've watched a few racers go back to 1x setups (we are in the home of SRAM) with huge chainrings and they swear by them but meh. On this particular issue I would say you're more in need of easy shifting and deeper gearing than you are in need of "good" brakes let alone Disc brakes. The better the brakes the less predictable everyone becomes.