if vec.dot(vec) > some_distance*some_distance:
do_something()
might not be quite as obvious looking as:
if vec.length_squared > some_distance*some_distance:
do_something()
As to why you'd want to use length_squared over length is that length uses a square root, which isn't always necessary for simple distance checks (e.g., closest object, checks like the ones above, ect).
vector * matrix
vector *= matrix
vector * quaternion
vector *= quaternion
Use the reverse order instead, enable WITH_ASSERT_ABORT in cmake to promote the warnings into errors.
