Yep. I know this full well as I've done quite a bit of experimenting with BP in a 44-40 Sporting Rifle. I found that a bullet cast from an NOE mould that indeed has a large lube groove worked great, even with beeswax-based "smokeless" lube.
I guess I'm a little perplexed at how the original loads from 130+ years ago worked with a similar bullet having only two smallish lube grooves.
CHT
Some food for thought on yr last question
First off we gotta acknowledge that any of those old guys that shot a lot were at least as gun savvy as the best around today.
1) Powder quality - it all goes kaboom and mostly it does the job ok - but there is a huge difference in the fouling level of different powders - something I kinda knew but got a good lesson when I started to make my own - willow charcoal homemade is streets ahead of Goex, Sheutzen (aka Wano), and most of the chinese fireworks powder - that said - thirty years ago we bought one lot of chinese fireworks powder that burnt beautiful clean - (never shot Swiss so I dont know about it)
2) A close look at those old molds - most of em got decent lube grooves - bigger than most modern molds - not anything like the excess of the big lube molds but better than a smokeless mold.
3) Realistically - how many times did those old timers shoot more than five shots at any target ?
4) Some of em got in a fight or two - mostly the target would have been big and close - nerves probably played a bigger part than accuracy
5) If its your scalp on the line and you been at it for a while you would likely do ANYTHING to keep that gun shooting - including pouring part of the contents of your water canteen down the barrel during a lull in hostilities - for an instant cleanout and a bit of cooling - so what if some gets in the action - later is a good time to fix that.
We dunno - we were'nt there - but its interesting to ponder on.