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Now let me get this straight.

Scientists spend from 6 to 10 years and tens of thousands if not hundreds of thousands of dollars learning everything they possibly can about a subject, including the implications and logical consequences of the processes behind that subject, then spend the rest of their lives increasing not only their own but science's in general knowledge, by actively researching and developing tests based on their intimate knowledge of those implications and logical consequences, yet when those very scientists, in all likelihood years before you were born, develop a definition of transitionals, you decide to latch on to a definition expressly designed by people of your like mind to present a false image of transitionals that is much easier to refute than the scientific definition and then require the rest of the world to adopt that strawman.

What makes you believe your opinion is valuable enough that the scientists who work in the many fields related to evolution and who collectively define terms which they use on a daily basis, should adopt your obviously half thought out and mind numbingly ridiculous redefinition of what constitutes a transitional fossil?

This all coming from the person who figures birds should retain reptilian respiratory system despite the fact the demands on the system are quite different. And you call me stupid.

Since you are obviously stuck in your own little world where you can pat yourself on the back for being wrong I'll address the rest of my post to the lurkers.

One of the main concepts of Evolution is that new features are derived from already existing features which acquire new function through variation in the genome and selection forces. There is also a reciprocal to this that features acquire morphological changes because their function is changing due to selection processes. The morphological change coupled with the functional change sets up a feedback loop. And yes, feedback loops are ubiquitous in nature.

The upshot of this, contrary to some who believe themselves above the thousands of highly intelligent men and women practicing science in the related fields, is that transitionals do not exhibit partial wings, partial limbs or limbs which are half and half.

In the case of the wing, a wing at its essence is a nothing more than a modified forelimb. For the scenario of a partial limb to arise, the existing limb would have to degrade to nothing either before, during or after a completely new appendage, the wing, grows at a nearby but different location, or the limb would have to at some point be half wing and half limb (from the shoulder to elbow a wing and from the elbow to wrist a normal limb). This is baldly ridiculous on the face of it.

For the bird wing to develop from the dinosaur forelimb it would at no time be a partial wing, either in morphology or in function.

Feathers, pneumatic bones (bones with air-sacs - light and strong), and fused clavicle (wishbone - to help support the increased muscle mass) all existed in theropods before dino/birds such as Archaeopteryx took flight.

Feathered fore limbs are not half wings but are as fully functional as the limbs of any other dinosaur. To change to a semi-gliding dinosaur all that needs to happen is the membrane (skin) which normally is attached at points along the limb to move its attachment points. This is similar to flying squirrels, flying lemurs, and bats as well as those few humans who have webbed fingers and/or toes (and no, I'm not suggesting that humans could fly. I am just showing that attachment point movement happens without decreasing function). Moving the attachment point does not produce a half wing. It does however, increase the surface area of the limb giving loft when jumping.

As the membrane increases in area, the ability to glide improves. During this time increased muscle mass and deepening chest would develop simultaneously.

Note: At this point the gliding dino does not need the modified respiratory system. Archy probably did not have an avian respiratory system yet apparently could fly.

After the maximum lift surface has been acquired, again through no steps that leave the dino/bird with partially formed or non-functional wings, the only way to increase lift is to lengthen the limbs, or in the case of bats and birds, the fingers.

There is nothing prohibitively costly in any of this.

The change from a gliding wing to a flying wing can be accomplished without experiencing a non-functional or partially non-functional half wing. To suppose that a half wing is necessary at any point is nonsense.

This needs to be repeated - At no time in the evolution of the reptilian (dinosaurian - theropod) fore limb to avian wing does the evolving limb experience a period of non-functionality or 'half' existence. The belief that the transitionals between theropods and aves must exhibit a half wing is utter nonsense.