Brake Rub during seated efforts?

I have a few questions about brake rub during seated efforts and how to prevent it. If anyone on this forum has the time/experience to shed some light on this I would be grateful for advice.

My questions:

-Does everyone on here over 80kg get a bit of brake rub during max seated efforts on a road bike?
-How significant are the losses due to this rubbing under load?
-Has anyone had this problem on a bike with a chainstay mounted brake?
-How do I prevent or minimise rub on my personal bike (without buying a different bike)?

Background articles:
http://www.slowtwitch.com/Tech/Debunking_Wheel_Stiffness_3449.html
http://sheldonbrown.com/rinard/wheel/index.htm

Last week I went for a long ride with 40 odd people, most of whom were on wildly expensive bikes with deep section tubular wheels. The strongest guy there (maybe 75kg, Cervelo S5, DA, 808s) had audible and visible brake rub when climbing in the saddle. His brake was perfectly centred and the bite point seemed about average (I looked at a coffee stop) and he was riding at a low but reasonable cadence. I spent a bit of time sitting behind the guy and it got me wondering how significant the losses due to brake rub are. It seems nuts that someone has paid a small fortune for a super fast bike and wheels this still occurs. As the day went on we punched it up several small hills and I made a point of riding behind several other larger guys (One guy with ENVE smart set/BMC team machine, another guy on a pinarello with something deep, carbon, and Campy without too many spokes, and a third guy on 404s on an older Trek Madone and in all instances brake rub was audible (I did not closely examine the other bikes)

I am a heavy, mediocre cat 2 and I ride an Allez DSW in 58cm. it was a warranty replacement for an older Allez elite frame that broke at the drive side dropout. When the warranty frameset arrived I built it up with the old parts except for the front mech and a BB30 crank. The new bike was more comfortable, lighter and in every way more pleasing except for increased brake rub with every set of wheels I own (28 hole ultegra 6600/DT R460 db spokes, 32 hole DA 7700/reflex db spokes, 36 hole DA/open pro db spokes, 28 hole 7900/reflex CD 2.0 spokes. clinchers at ~110kgf drive side, reflex sets at a bit less) I run my brakes with the bite point pretty close to the bars and have 7800 sti and calipers. the centre of my pad contact is roughly 157 degrees from my contact patch. I was thinking of buying a mega stiff deep section wheel, but maybe that would actually make things worse?

The slowtwitch article claims that high spoke count and flexible rims prevents rub, but for me this has not been the case. There is a graph on the Damon Rinard arcticle about halfway down showing deflction in relation to rotation from the contact point for whole bunch of wheels. I couldn't find the key to the graph but did notice that the opposite side deflection near 157 degrees is not directly correlated to deflection at the contact point.

Even more questions:
-Despite modern frames and rims being more rigid, is this more of a problem than it used to be?
-Anyone on this forum bored enough at uni to do a project on it? Damon Rinard's crack at it was over 20 years ago.
-Would a QR rear hub with a massively rigid axle reduce dropout deflection and therefore reduce opposite side deflection? Maybe a 10mm Specialized Skraxle type thing inside a hollow oversized alu axle?

Thanks to anyone who has taken the time to read this, I would be grateful for any input or suggestions.

regards,
James

You could also post the (shortened) question in the below thread. It seems to have some knowledgeable posters.
http://www.lfgss.com/conversations/128002

Interesting that even the 32/36 spoked wheels rub. I see why you'd question rims and QRs might cause this (I prefer track/solid axled hubs, but I don't have massive problems with QRd hubs). But the thing that changed for you (when brake rub got more frequent) was the frame... maybe you're looking in the wrong place? Maybe stays are too flexy for you/your friends/everybody over 140lbs? I assume the frames you mention are all plastic?

Of course, you could just run your brakes much further from the rim. Or get disc brakes.

Yeah, disc brakes do kinda sound like the long term answer.. I just have the horrible feeling that if I buy a bike and two sets of wheels now it will all go the way of Betamax in a few years as axle standards evolve. And the issue of a racing double with short stays and a 135mm disc rear end. Does everyone just have shitty chainline?

I at first blamed my frame.. (the older model did have larger section chainstays and seatstays.) But if I am going to buy a new frame, I would want to have a better idea of what to look for (chainstay mount brake or seatstay mount? and would want to know if it will it rub with the wheels that I already own?)

If I could fix it by changing a rear wheel, that would be class. I just need to figure out what tubular wheel would be least likely to rub on the frame that I already own.

The pads are currently as far out as possible without loosing the ability to lock the wheel. I changed the cheapo brake housing for a DA9000 cable kit (with the polymer crap sanded off the clamped section) which slightly improved feel but didn't noticeably increase the maximum initial distance between the pads and rim. I thought about compressionless BMX brake housing, or running my hoods much higher on the bars to increase lever travel.. but haven't tried either yet.

I kinda wonder what the answer is for a pro like Kittel? He is both larger and dramatically stronger than me. Is his rear brake just rubbing constantly?

I figure there must be some people heavier than me on here who have figured this out.

I will try to make a shorter/more coherent version of the initial post later on and throw that up on the other thread.

thanks the the replies

Yeah, disc brakes do kinda sound like the long term answer

I'm a hefty unit and don't really get brake rub as such on my Aluminium Road Bike. On the verge of purchasing my first crabon bike so I'll see how that goes.
I do get (front) brake rub out of the saddle on a Giant TCX with TRP Spyre mechanical disc brakes. Not ruling out me being useless as setting up disc brakes however.

Now that you mention it.. my genesis disc cross bike had front brake rub on a carbon fork. Is your TCX still using a QR front hub? My cross bike was the bike that convinced me that QR hubs and road discs were not cool. I sold it after a winter of constant fucking with my brakes (cx75 recall, my qr front hub shifted in the carbon dropout and general annoyance)