this annoys me a bit, coilovers are for a purpose not for posing, if people just want them slammed on there arse buy short springs.
That is only true if you are using a single perch coilovers where lowering actually decrease the performance of the dampers as you are loosing damper travel.
On a "Dual Perch" setup, lowering the ride height will not cause any lost of damper stroke travel or change the springs pre-load, so technically so you are not loosing any performance by lowering the ride height.
Yes, it does put other parts of the suspension (bushes for example) under more stress, roll center changes, etc.
But the effect isn't HUGE and alot of the difference can be sorted out by using different alignment setting.
A set of suspension going too low is never a good thing on a car.
But at the same time, a set of suspension that couldn't go low because it isn't properly specified for the chassis isn't a good thing either.
The long as you have the "correct" range of height adjustment available, then it is up to the user to decide what is best for them.
This is the whole point of having adjustable suspension as you can decide what you want and achieve it.