Use of Than with Comparatives

[skumar94]

My question is for a rule mentioned in the Strategy guide on page 130 of the 8th Edition SC.
"Always use than in a comparative form."

Is this sentence wrong, without the usage of than?
His car is fast, but mine is faster.

[jnelson0612]

My question is for a rule mentioned in the Strategy guide on page 130 of the 8th Edition SC.
"Always use than in a comparative form."

Is this sentence wrong, without the usage of than?
His car is fast, but mine is faster.

It looks fine to me! We can make comparisons without "than"; however, if we use "than" it should be used to make a comparison.