Years ago after being completely off AAS for 7-8 yeara I used whey protein with creatine mix and it had very notable effects. Pretty much one of the only supplement combos I would say has dramatic impact on the physique. Hardening, drying and leaning. At that time I was doing a lot of grappling and a lot of weight training. That combo definitely was a performance and cosmetic enhancer. Probably would be great with a TRT regimine
OT, I think it's smart of you to still utilize creatine even while on TRT. I use to believe it wasn't necessary. The problem was, I was expecting a lot from the supplement. I can honestly say with consistent use, creatine is one the most beneficial supplement on the market. Without a doubt I notice and increase in strength while using it on a daily basis. In addition, my recovery has improved.
Just like others have mentioned, creatine offers other benefits besides muscle building. It still amazes me that guys that I know that work out consistently naturally still don't use the creatine. It's like they're so clueless on how beneficial this supplement can be. I've tried to beat this in my brother's head, but he just doesn't listen.
Depending on how much meat you are eating every day you can be getting a fair amount in already. I didn't notice a huge difference when I first started using it, but I was eating 2-3 lbs. of meat a day before I started using it.