If Mcap/Revenue is high, it suggests that there is a lot of forward expectations built into current price, i.e lots of premium in the price (it can either mean the current sp is potentially ahead of itself but it could also mean that holders expect large things from the stock (but of course expect is one thing, realisation or revenues materialising is another) . Conversely, if Mcap/Revenue is low, little to no expectations built in (it can mean market is expecting worse results going forwards (is that the case for CAT? dunno) or the stock is pretty much under the radar or yet to be appreciated or given due credit). Comparison between stocks is not to be looked at purely from a single metric of course as each have varying potential , but the metric serves to show where its valuation is presently at, relative to its most recent revenue performance.
