Originally posted by BlauK
Honestly,
at least I was interested in how you were doing it previously and what you achieved with it. Did you have the RPMs reversed compared to throttle, or what was the idea?
Please educate me 
... I am not saying I am right or anything. I just don't get the idea you had with the lincage.
It's obviously very hard to explain. But I'll try one more time, then I'll give up.
Low manifold pressure and high RPM produces drag from the props, slowing the gain of speed in a dive. Don't get me wrong, this is beneficial in many cases. But if I'm say 5k over the enemy, I want to be at my maximum maneuverable speed when I engage them without much of a thought process.
I attain that speed by chopping both the throttle and RPM for my dive. This produces less drag and my speed increases much faster than with the prop windmilling at full RPM. As I pull onto my target my speed begins to decrease, so I increase both throttle and RPM to maintain my attack speed.
The key here is the dive and the speed reached withing a given amount of altitude. If I were to leave the RPM set full and try using the manifold pressure to adjust speed, it would be a nightmare. In a dive, the prop is usually spinning faster than max RPM and adjusting the manifold pressure within a small range does little to nothing because of that. So the drag is still there until you reach a break point where manifold pressure actually does something. By that time, you're either under speed or way over speed.
With RPM linked to the throttle, the RPM increases and decreases in proportion to the manifold pressure which increases or decreases drag from the prop giving much better control in a dive.
Keep in mind I don't fly single engine planes very much so I don't know if the effect is the same on them.
Seriously, try it offline. Take a 110-G2 up to 10k, get to cruising speed and chop just the manifold pressure. Then go into a reasonable dive. Say you want to get to 400mph. Watch your speed and altitude and remember where you hit that speed. Now climb back to 10k and repeat, but this time chop both RPM and manifold. You'll find you're at speed at least 2 to 3k earlier than the other way. Gradually increase both manifold and RPM together and you should find you're easily maintaining speed and control.
If you want to take it a step farther, repeat again and see how difficult it is to attain and maintain speed using just manifold pressure within the same distance as chopping both RPM and pressure.
Now landing is a different matter where you want RPM separate from manifold pressure. But, that's another story.
Edit: I've already plugged in my spare X45 and linked it's throttle to RPM, so this is all moot at this point.
