Most people put them a couple of inches behind their handlebars (see pic, these are the old Vuka clamps / pads which were the best, but with other extensions) so that they are not in such a stretched out position when on the aerobars.
Or you may even want them in front of your handlebars - I once did that on a road frame I converted to a TT bike.
I think those ones are terrible as you can't slide the bars back and forward in the clamp to adjust how far the bit you hold is ahead of the pad. That, combined with having no back / forward pad adjustment means you basically just get one position, which is highly unlikely to be the one you want. You have to adjust your position to fit the aerobars, not the other way round!
You lot need to work on your hamstring flexibility
That is true, but it depends on your frame geometry, how long your top tube is, setback, etc. It's definitely something that you need to be able to adjust - so my bike fitter tells me!
Most people put them a couple of inches behind their handlebars (see pic, these are the old Vuka clamps / pads which were the best, but with other extensions) so that they are not in such a stretched out position when on the aerobars.
Or you may even want them in front of your handlebars - I once did that on a road frame I converted to a TT bike.
I think those ones are terrible as you can't slide the bars back and forward in the clamp to adjust how far the bit you hold is ahead of the pad. That, combined with having no back / forward pad adjustment means you basically just get one position, which is highly unlikely to be the one you want. You have to adjust your position to fit the aerobars, not the other way round!