Habitues of the porch and sons thereof,

several times in the last few years I have read in a blog or article or
some other account, of folks using thin paring chisels honed to 20 degrees.
They are often mentioned in the very final paring of dovetail base lines.
If I recall,  these are almost always old tools of Sheffield origins.
Anybody set up like this? Anybody have any to sell.  Are they really
significantly thinner? Does that, in fact, matter?

Thanks

Ron. A Kokomo Galoot who is looking forward to a day in the shop tomorrow.