In a broad and sweeping generalization, by far the most reluctant use of a fusion engine comes from those that are not of the Taurian faction. It is hard for one to understand perceived need when they do not have the need themselves, nor can the length to which one will go to obtain that perceived need be understood. I good man will steal a loaf of bread if he is left with no other alternative.
The first issue is one of military necessity. Does the TC need to build the tank itself and why is outside purchase not reasonable? One of the ultimate goals of a military is to maintain sustainability, or self sufficiency. A military that is reliant on outside source is susceptible to supply interuptions outside of their control as well as that source being attacked or interupted. The interupted supply of a primary combat vehicle is unacceptable when a reasonable alternative is available. That alternative is a MBT being built in the TC. That does not include building a MBT at an exterior TC location like Perdition, which can also have its supply chain interupted, but a location of reasonable security like the Hyades Cluster.
The next two issue to address is a need for a Main Battle Tank and what role will it fulfill and how will it supplement what the TC already uses. The role for a MBT is addresses above in the current TO&E's inability to defend against assault forces, supported by the Chaparral's canon, and a TO&E that previously had the Rommel listed. Errata reasoning was the technology and origin, not need or role. If there was no need for one, one would not have been designated to fulfill that role and the Rommel errata would not have been needed due to that technology. The role that is most often suggested, has been a MBT. Predominant criteria has been the ability to threaten any mechs on the battlefield, be effective at holding off enemy battlemechs until local battlemech forces can arrive and support our own heavy battlemechs forces in offense. Primary weapon so far discussed has been the AC20, and the need to support heavy battlemechs dictates a speed of 4/6. The logical solution is the use of a fusion engine to fulfill that criteria.
The final objection is specific canon objections to a fusion engine. All canon arguments that have been brought forth, have either had their validity reduced or completely discredited. The objection to the TC using fusion engines in their vehicles is discredited with multiple uses including the Gabriel, Cyrano, Chaparral, J Edgar, Hunter, and the numerous other vehicles that the TC supports. They include industrial capability to build the engines, which included 2 separate canon factories that already build them. The ability to create, adapt or restart a line to produce them has been countered with canon proof that the Taurians have already done so even at the battlemech production level without outside help. The issue of the number of engines available has been countered with canon reference to increased production, and determination that the canon put forth was a specific instance.
In summary, substantial argument has been brought forth to support the need, role, criteria, and ability of the TC to have a MBT produced in the TC. Development of this tank should be era specific as a replacement of the Rommel Tank, pre 3025 to present (reasonably much earlier and could include Star League link to original refitting of factory by Star League after the Reunification War.)
It is in my recommendation that TC faction members proceed with development based on need, role and criteria in efforts to present a thorough presentation to the writers. Ultimately, the decision will be in their hands and a thorough presentation can only help our cause. A second recommendation would be to focus on progressing forward on the issues of need, role and criteria like weapon load definition, possible new weapon technology incorporation, etc.
Keep posting your ideas