The issue seems to be more visible when looking along the X axis (/tp @p ~ ~ ~ -90 0 /tp @p ~ ~ ~ 90 0)
but it can also be seen on the Z axis (/tp @p ~ ~ ~ 180 0 /tp @p ~ ~ ~ 0 0)

Steps to reproduce:

1. Place a minecart in front of you
2. Run /tp @p ~ ~ ~ -90 0
3. Walk foward and backwards repeatedly till you see it (only happens for a few frames)

Observed Results
Gaps in the model

Expected Results
No gaps