When you do want to use the skimmer vs the drain on an inground pool?

I have used the "ICK" Stractor on an above ground pool for years and it does a good job of gathering leaves and some debris but does not filter the water. It is made of material similar to a leave net and attaches near the return via velcro and floats on the top of the pool to catch leaves, etc. Never heard of it being used on an in-ground, but if the return was up where you can get some force to keep it floating it would probably work.

I have installed The Dragonfly Super skimmer in in-ground and above ground pools

for a number of years and have found that it does a very good job of gathering leaves, debris, pollen, dust, industrial fall-out etc, It is a floating skimmer and if set up according to instructions will remove nearly 100% of floating rubbish from the pool it's a suction-side cleaner so every thing it catches goes directly to filtration via the leaf basket. If you want more info on it Have a look at the related links below (Pulse surface cleaner) for the inventors website.