After seeing Mike Watt performing with Iggy Pop for a few minutes on TV, not to mention watching some Cliff Burton videos, I decided to lower my strap. Before, I was playing pretty high, i.e. the body of the bass resting against my abs.
I dropped the strap length so now I play it mostly against my waist an thigh. Holy crap, what a difference. Firstly, it just looks plain cool - I can actually rock out a lot more now. Secondly, it has a noticeable impact on how I play. I have to sacrifice my left hand, since playing lower means having to curl that hand up or play more upright, which means that fast scales and such are a limited possibility unless I lessen the strap length, sit down, or lean up against something. It does, for better or worse, keep me from wanking near the higher frets unless it's in short bursts, which sounds better to me. But the difference it makes on my right hand and arm - holy cow! Where I would cramp up before with fast runs, triplets, rakes, etc, I can now play my parts with ease. It's very hard to get tired now, and since I like to play straight up rock, my left hand doesn't have to be all over the place, and I can play at crazy speeds. Plus, it's WAY easier to implement the Geddy Lee flamenco technique.
And, again, it looks way cooler. Especially with my jacket and cut-off gloves.
Any of you guys notice a difference in your playing depending on strap height?