As a high ranking reaver, I assume that you've fought captains 1v1 before. I'd be interested to hear if you've ever been beaten by one traited red since u12. I spar relatively frequently with Ahtaaja (r11 reaver) and in red I don't really stand a chance even when popping OB. In yellow, the result is closer to 50/50, depending on lucky impale devastates/ success of my early hits on him. Needless to mention that SoD and LS aren't used. Now, if I am facing a pile of high rank creeps (on Monday I think there was Valdez, Enco, Weewoo, Uss and a couple of others - each of whom could kill me solo - plus a few greenie followers), and they are grouped up against solo freeps (about 5 of us total, and I was the only green rank there, others were red and blue), should I go red just to give those creeps free infamy? I have never minded dying - I'm a melee class, it rather comes with the job - but if I'm not going to get a decent fight/some kills out of it, I don't think the death is worth it.
That's why in those circumstances I go yellow, and I'll stay in yellow vs any high rank creep because 1) high rank readers can destroy red cappies without breaking a sweat, 2) decent shadow wargs can have me half dead before the CC break comes into effect, and 3) with high rank defis and WLs, it just turns into a power-battle, which the captain inevitably looses. I try to play red as often as it is feasible, but in the circumstances explained above, there are times when red feels rather futile.