I'm trying to settle a debate with my girlfriend. She says "how quicker" is incorrect and you should always use "how much quicker".
Which of these is [more?] correct?
See how quicker the cars flow into the city than out of the city.
See how much quicker the cars flow into the city than out of the city.
I can't find a definitive source. But Googling indicates the former is less common (5,300 results) than the latter (320,000 results). But most of the hits for "how quicker" are in Google Books, especially texts from the early 20th century.
Could this just be an archaism? Has the grammar changed? I'm assuming those old books were lectored.