ha, i wish it made me all smarter and whatnot. probably just some product of how i learned/what i read/amount i read at what point in life. everyone learns to do stuff differently i guess.
the wiki article, which is pretty brief and had a definite opinion, says:
"At the more powerful rates (memorizing,
learning, and reading for
comprehension), subvocalizing is very detectable by the reader. At the less powerful, faster rates of reading, (
skimming, and scanning) subvocalization is less detectable. For competent readers, subvocalizing to some extent even at scanning rates is normal."
for anyone worrying about it keep that in mind. people who dont subvocalize much are likely to do it more when they're under pressure (time or needing to remember everything in the paragraph, or having trouble understanding it). i'll back that up anecdotally. and depending on how you personally process stuff, doing it even at quick but casual rates where you're not freaking out about details is normal, which others here back up.
so, if you dont subvoc then doing it is slower, but if you do subvoc then trying to not do it may cost you similarly. dont worry too much about it, read regularly to get in gear, and +1 to above whoever said that you're probably better off reading at your rate so you can answer the questions more easily vs skimming and having to reread later 3x...