Comment by elphinstone

I believe it's a bit more nuanced than that. Short ubiquitous words like "and" or "the" we instantly recognize at a glance, but long unfamiliar or rarer words we read from the beginning, one syllable or letter at a time, until pattern recognition from memory kicks in. All unconsciously, unless the word is so odd, out of place, mispelled, or unknown that it comes to conscious awareness and interrupts our reading.