Repeat after me...a texas tommy is just a swingout. Just a swingout...
More specifically, a texas tommy is ultimately linear directionality. However, it's easy to over-rotate and curve out of it rather that straigthen out of it. For me, this has been happening because I get anxious about making it through the spin and weird hand position of the turn and so tend to a) speed up/rush through it and b) as result, over-rotate out of it so I keep just spinning off to the side rather than slowly unfurl out into what would be a linear endpoint. It's hard. I'm working on it.