That assertion seems to be completely gratuitous. Men who have kept their foreskins are men in their natural state. I don't see how blow jobs can be better without the foreskin than with it. Having a foreskin gives you other options that a circumcised penis doesn't. But I can see why someone might think that an uncircumcised penis is less appealing if it is not kept clean. Otherwise, it's all balloney. I'd make sure my thing was nice and clean when indulging in blow jobs, but then again, there are those who'd find it too clinical.
Although smegma may be unpleasant, I'm not sure that it doesn't have a protective side to it. Any man who uses his penis regularly, and washes should not have any problems with smegma.
In males, smegma helps keep the glans moist and facilitates
sexual intercourse by acting as a lubricant.
[4][5][6]
Smegma was originally thought to be produced by
sebaceous glands near the
frenulum called
Tyson's glands; however, subsequent studies have failed to find these glands.
[7] Wright states that smegma is produced from minute microscopic protrusions of the mucosal surface of the foreskin and that living cells constantly grow towards the surface, undergo fatty degeneration, separate off, and form smegma.
[4] Parkash
et al. found that smegma contains 26.6% fats and 13.3% proteins, which they judged to be consistent with necrotic epithelial debris.
[7] Newly produced smegma has a smooth, moist texture. It is thought to be rich in
squalene[8] and contain prostatic and seminal secretions, desquamated
epithelial cells, and the mucin content of the
urethral glands of Littré.
[6] Some state that it contains anti-bacterial enzymes such as
lysozyme and
hormones such as
androsterone,
[5][6] though others dispute this.
[9]
According to Wright, little smegma is produced during childhood, although the foreskin may contain sebaceous glands. She also says that production of smegma increases from adolescence until sexual maturity when the function of smegma for lubrication assumes its full value, and from middle-age production starts to decline and in old age virtually no smegma is produced.
[4] Oster reported that the incidence of smegma increased from 1% among 6-7 year olds to 8% among 16-17 year olds (an overall incidence of 5%).
from Wikipedia[url=http://en.wikipedia.org/wiki/Smegma#cite_note-9][/url]