https://www.patreon.com/posts/flash-balance-110965929

This post is allllll about balance. The video explains it in more detail (and if you have just a few minutes then I highly recommend you watch it), but the main point is that actually adding weight to the overall rig that you're holding can sometimes help with wrist pain.   This is one little nugget of gold that comes up when I talk about bounce flash during my workshops, and something I've been thinking a lot about while reviewing the new Canon R5ii. I'm not particularly happy with the r5ii, but I still haven't hit my 10k threshold yet. Soon enough I'll share my full review here.  Even though I might not keep the r5ii... I've missed the modularity of a a body grip since switching to the permanently gripped r3. The main reason is because the battery grip lowers the overall center of gravity, which is particularly apparent when you throw a speed light on top of your camera, and makes it muuuuuuuch easier on the wrist than a non-grip body that ends up being front heavy.

https://filextras.com/7zvsrk3ogtej/Flash___Balance__Why_You_Might_Want_a_Battery_Grip.rar.html