2t's detergent package (low ash) is usually more suitable to higher hp per cc engines like watercraft. Not that tcw3 can't take the rpms or load, many ski's advise using it. It's more that the internal engine temps are higher and can "cook" some of the oil, without the detergent package to clean it this "cooked" oil can gunk stuff up. A low output per cc outboard with constant fresh water cooling can get away an "ashless" tcw3 oil because it doesn't get hot enough to "cook". A good indicator of the heat internally is the heat range spec'd for the sparkplug. Engines that run plugs that run at the colder end of the chart might be a good candidate for an low ash detergent.
The tcw3 is more than capable for power and rpms at the right ratio. A high output engine that fails using it usually is a result of a stuck ring, NOT lack of lubrication. A lot depends on the actual oil IMO, I've seen, rebuilt and have buds that run some pretty radical hardware on tcw3 with great results, but not any tcw3.
You may hear a lot about rotax's requirement for low ash. Besides the exhaust valves (engines don't fail from stuck exh valves) and high hp/cc output there is another reason that isn't often mentioned . Dykes or L shaped rings are used on many of their builds. This top ring design is a little more prone to getting gunked or carbon in the lands. This can lead to major engine failure so they're pretty insistant on not using tcw3. Again I've seen some (not all) tcw3's work very well on these motors too so it may be considerd good advice but not the rule. Some may say yes but Yamaha's and others use TCW3? they also use a conventional semi trapz ring so they're probably not so worried about sticking a ring.
