Laptops, notebooks, MacBooks or any of those tiny form factor, slim, poor excuses for a mobile desktop rely entirely on 2 things. The battery and the cooling solution.
When you bump the power factor by overclocking, you take an already taxed heatpipe and add wattage it wasn't designed for. That adds an exponential amount of heat, and thereby problems later. Sure, you'll get a benchmark a little better, but once the laptop heats up with continuous usage, you'll find it's pushing thermal limits if not throttling already. Taking a stable performance, adding instability (OC Always add a small amount of instability at a minimum) and ending up with the same, if not worse, fps after an hour of gaming.
It's a laptop, not a desktop. The low power 25w TDP cpu will not take to higher clockspeeds and the unintended higher power draw, well and the very minimal gains are not worth the added aggravation.