I can't think of any situation where an original gun in serviceable condition will be sleeved - the barrels are in acceptable condition.
Although I am unable to give any statistical numbers here I can very well recall when Sleeving was highly promoted as a method of putting "Damaccus" bbl'd guns into service. I highly suspect a good number of these were sleeved which in fact had good servicable bbls. This was a Pity. I don't think this is being done much anymore,thankfully.
I find no fault to sleeving a set of unusable bbls if the gun otherwise warants it. The cost simply has to be compared with what can be found in a similar price bracket for a gun with original bbls. I would not for instnce give the same amount of dollars to sleeve a gun as what I could buy the same model gun with good original bbls. This would let out sleeving most of the guns I own. I have for instance an H grade Lefever with unusable bbls & a cracked stock. For I also mhave some more H grades for which the combined total I gave for them would not put this gun back in service. It would simply not be cost effective, so I keep it for a parts gun.
