Still small blades for me and any shorter than 8" over (for surfing) causes me to bend over too much to fully dip the blade.

DJ

I currently have a blade that is too big. I liken it to cycle training on hills with heavy wheels - I think it makes me stronger and forces me to concentrate on form.

My only paddle I am using at the moment is the QB Big Mama Kalama with 10" blade. I Like to mix it up with my 9" blade (until it went missing 2 mths ago). After paddling the 10" for a few sessions I would go back to the 9" and it felt like I was pulling a 7" through the water. I see it a bit like athletes that train at high altitude then go back to normal training conditions.
As much as I enjoy paddling with my 10", I do miss my 9".

I remember reading something somewhere that made the most sense on this topic.

It was basically that rather than having a paddle blade as big as you can get away with having a blade as small as you can get away with.

The reasoning is that if you watch video of people paddling the blade enters and exits the water at the same place.

If the blade is too small it slips, this is inefficient, it will require a higher rating with less pull meaning it feels easier but to go faster probably way more fitness. Too big it creates no advantage to a correct sized blade as it holds in place anyway and is heavier and creates more drag on exit, recovery etc.

No need to be huge but just big enough to ensure that when used with a good catch does not slip through the water. A stronger guy will need a bigger blade to hold in place. Most important though is a good catch...