The benefit of having Triple Strength Myomer Implants is already reflected in the unit's stats prior to conversion (increased armor, ability to use more support weapons and not be encumbered, etc). There's no additional conversion bonus not already reflected in those stats.
For example, Tau Zombies from Technical Readout 3085. They have 4 Heavy Support Lasers for a 6 man unit. The Heavy Support Laser usually has a 3 man crew. Without the Triple Strength Myomer, they could only carry 2 Heavy Support Lasers, not 4.
Also, it does more damage at range 0 due to TSM Implants, though it doesn't happen to help the unit in this case. Their standard 7 damage out to range 15 is 1 damage in Alpha Strike, same as their 8 damage at range 0. It just happens to not be significant for that unit at Alpha Strike scale.