We recently had our stays both off to polish the bowsprit and replace the knights heads with SS ones. The mast stayed up just just fine with the lowers. Although we did tie off the halyard to the bow before leaving. We've both been up the mast several times with the fore-stays off.
When we were cruising we had just one 45# CQR on the bow. Then our friends on their HC 38 almost went on the rocks. They entered the anchorage under sail and dropped the primary anchor, a Rocna and it it did not set. Then started the motor and put it in gear, but nothing happened. They managed to get the secondary anchor, a Bruce to set before hitting the rocks. It was found that grass had wrapped around the hoop of the Rocna and a large line had wrapped around the prop. The boat would have been severely damaged or lost without the secondary anchor. We immediately put our Bruce on and now cruise with two anchors, except when sailing in home waters.
Our CQR has 330' of 5/8" high test that goes through the anchor platform in 4" ABS and is pulled back to the mast. The Bruce is on 250' 3/4" double braid which rides in the anchor locker.
Jim