True, but I generally do not usually need try to reduce a simple expression like a*b/c.
Part may seem a bit peculiar, but the parts are generally split up at the parenthesis level and addition levels.
It will also split at addition and subtraction so:
y=(a+1)*(b+1)/(c+1) + (a+2)*(b+2)/(c+2)
So with a little thought and perhaps a dash of trial and error, one can extract the relevant sub expression without great difficulty. Also, Numerator and Denominator will let you select the entire numerator and denominator, so if one really wanted to work on a*b/c, you could use them.