Trouble writing/drawing and GST?

I'm trying to find out how much of an impact GST is having on my ability to draw, paint, and write. Long story short, over the years I developed bad drawing form and it led to way too much tension in my hand and forearm, which led to tendonitis (now basically gone) and a frequent inability to draw or write without tensing my hand very tightly.

 

Some days it's no problem, other days it's a battle just to make straight lines without clenching. I haven't found a pattern between GST this issue though, i.e. it doesn't always get worse on days I work out before drawing.

 

It's very frustrating and I'm trying to see if anyone has had any issues, insights, or advice....

I do the wrist stretches all the time, as well as something similar to the elbow/forearm prehab routine found in a video in one of the mobility stickies. I haven't tried rolling out my forearms on a regular basis though.

It's not so much forearm tension as much as its hand tension. My guess is just that sometimes the muscles involved get worked pretty good doing things like handstand work and it makes my hands weak. But like I said, it's doesn't always happen on workout days.