OP sorry to hear you got knocked off - was it because you couldn't stop in time or something, were you riding to close to the back of a car? The whole experience would be pretty disorienting for you that's for sure, but as you didn't say what happened we don't know if it was your fault or someone else's ie are you ascribing your lack of a rear brake to the accident when in fact it was because you don't check over your shoulder enough? Or it could also just be bad timing around a shit driving that's got nothing to do with your lack of a rear brake? You see what I'm getting at? Riding fixed means you have rear braking ability and a front handbrake so you have to ride within that context/skillset. If you're doing so then I wouldn't say that adding a rear handbrake to your fixed would prevent you getting knocked off.
OP sorry to hear you got knocked off - was it because you couldn't stop in time or something, were you riding to close to the back of a car? The whole experience would be pretty disorienting for you that's for sure, but as you didn't say what happened we don't know if it was your fault or someone else's ie are you ascribing your lack of a rear brake to the accident when in fact it was because you don't check over your shoulder enough? Or it could also just be bad timing around a shit driving that's got nothing to do with your lack of a rear brake? You see what I'm getting at? Riding fixed means you have rear braking ability and a front handbrake so you have to ride within that context/skillset. If you're doing so then I wouldn't say that adding a rear handbrake to your fixed would prevent you getting knocked off.