I'd say it's about risk management. And consequences. What is your rear wheel? Rim? Number of spokes? How much do you value your chainstay paint? (I'm assuming steel; this being C & V; carbon fiber changes this one a lot.) Do you carry a spoke wrench and know how to use it? DO you have an acceptable back-up plan? (The call of shame - NBD or martial no-no?)
Two broken spoke scenarios I witnessed. Both on bikes with "plenty" of clearance. First, myself in 1979 on my brand new Peter Mooney. Saturday morning. Santa Cruz Cycling Club ride. Town line sprint. A strong but inexperienced rider put his rear wheel where my front belonged. Eventually I had to return my wheel to under my weight or I was going down at 30 mph+ (and the next half dozen behind me). To stay up, I leaned my wheel into his rear and pushed off. Worked, but - his quick release cut out 8 consecutive spokes! I rode the bike to a standstill with a wild once per revolution throb.
My 28c clincher was rubbing solidly against the fork under the crown and had polished the bare steel. Outside that and a few missing spokes, no damage at all. Wheel went thousands more miles. The fellow on my wheel was a complete stranger but upon my bike handling saving his skin, he turned around in gratitude, got his truck and drove me home. (Robert Wright, gifted bike mechanic and author of a very good and equally simple book on how to build bicycle wheels.) Oh, I was riding the wide Weinmann rims with 36 spokes. I doubt a stiffer side-to-side semi performance rim has ever been made. And TG! Saved my butt.
Other scenario - rider in a small group broke a high-tech, non-steel spoke on a CF bike and rim. No spoke wrench and he had so few spokes to work with I"m not sure it would have helped. The tire had already done a little CF damage to the chainstay. They were debating options. Not my ride; they were complete strangers and I had nothing on me that could help so I rode on. I don't know what he chose to do but already., his bike had suffered more than mine for a far less consequential mishap.
With aluminum rims (I've never owned CF), enough spokes (32, 36), a spoke wrench and a modicum of skill with it, you can often juggle the spoke tensions of the remaining spokes to ride home. If your fork and frame are steel and some hard to see paint scrape is OK, you have little to fear of a spoke breaking, even with very close clearances. (But at speed, you may kill the tire with sidewall wear, especially if you are riding a thin walled performance tire. The medium priced Paselas would not take kindly to that sidewall wear at all.
Look at what you've got, decide what is acceptable and what isn't and go from there.