Speed kills, as they say.
TTSX plus speed can be devastating. Here's a pig hit by a 120 E-Tip (very similar to TTSX) out of a 26 Nosler at 3,450 fps.
I like to try balancing bullet design with velocity. Monos reportedly don't have a velocity ceiling. But, I've had less than good results on WT's with low S.D. TTSX at hyper-velocity. Probably OK on 'yotes, etc.
I don't like to use monos with a S.D. below .200 in high velocity rounds, such as the 80 gr. TTSX at 3,600 fps out of a .240 Wby. So, in practical application, I think monos do have a functional velocity ceiling on WT's, etc., which is S.D. sensitive.
DF