To go way back, they were not soaked in Kerosene or "Coal Oil" as it was not invented til 1870 ? or something like that, by a guy in Canada & it was not mass produced for sale til the late 1800's and then it was way too costly to waste on soaking a ramrod in. All of this soaking theory stuff came into view in the 1900's.
From what I have heard & read & from what my grandad told me, the reason they did soak them was not to strengthen them or make them more flexible, but actually was done to keep them from deteriorating from cleaning the rifle in water. Thus if it is impregnated with "Coal Oil" it would not take on any water from the cleaning nor would it dryrot for years.
Besides all of that, I have never seen a reason today to soak one with the preservatives we have today in our oil & our finishes. If it is a good straight grained rod & you use it correctly you most likely will never break it. If/when you do break one, study why it broke, where it broke & the technique as it broke. I have broken 3 ramrods in 35 years of ML shooting & I have owned and shot a bunch of ML's. Tow of such were broken because of a notch or ring cut in the rod years ago & the other one was broken years ago trying to ram down a Minieball & it broke at a knot in the rod.
IMHO, Ramrods are usually broken usually one of these ways:
1: Twisted off at the tip because of stuck ball or patch.User Error.
2: Knot in wood or grain runout & shaft broke at this place.
3: Trying to use too much RR when raming a ball down. User Error.
4: Notch or ring cut in rod to mark load. Unecessary & User Error.
5: RR came out of rifle & caught on something & snapped it off. User Error. Ramrods should have enough bow in them to hold them in place or go into a snug RR hole to retain them.
And of course again this is just IMHO. But we are talking about a $3 ramrod & a piece of PVC pipe & .50 cents worth of kerosene. So if ya want to try one go for it & see what it does. Never hurts to have an extra rod around ready to tip anyway & if ya need it you will have it.
Custom Muzzleloaders & Custom Skinning Knives