ID 346563 - Transform nodes motion blur option gives varied results from non-processing nodes upstream

Problem summary
Within a Transform node, you can apply motion blur to keyframed values through increasing the 'motion blur' value.

If you have an upstream node that does not process or alter the image (eg. Grade with no alterations), and feed it into this Transform node, the motion blur will be assigned as expected.

Although, if you create two different nodes (eg. Grade and ColorCorrect), and run these two nodes through two separate Transforms (with the same values). The results between the two Transform nodes will be slightly different, even though the upstream nodes have no set values or changes

If you look at the image data before the Transform's are added, there are no differences and if the nodes are of the same type, there are no differences.

Customer reported version
nuke.10.0v5

Customer reported platform
rhel5

Steps to reproduce

Open up attached script and view the result of the Merge (Difference) node.

or

1) Open a new Nuke script

2) Create a 'Checkerboard' node

3) Create a 'Grade' node (with no added values)

4) Create a 'Transform' node and set a keyframe at Frame 1 at translate x to a value of 0

5) Go to frame 100 and set a keyframe at translate x to a value of 100

6) Go back to frame 1

7) Create a new stream from the 'Checkerboard' Node and create a 'ColorCorrect' node

8) Copy or Clone the 'Transform' node from step 4 and place below the 'ColorCorrect' node

9) Create a 'Merge' node and set operation to 'Difference'

10) View result of 'Merge' (Difference) node
Result: There is difference between the two results of the motion blur in the 'Transform' node

Node Tree diagram
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11) To confirm this is the Transform node, compare the Grade and ColorCorrect nodes in the viewer
Result: No differences

Workaround
The only viable workaround is to ensure that any nodes that are running parallel in each stream are of the same nodal type in the same nodal order

workflow diagram
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Reproduced by support
This bug has been reproduced in:

Nuke 11.1v3 - Windows 7
Nuke 11.1v1 - Windows 7
Nuke 11.0v4 - Windows 7
Nuke 11.0v1 - Windows 7
Nuke 10.5v7 - Windows 7
Nuke 10.5v1 - Windows 7
Nuke 10.0v6 - Windows 7
Nuke 10.0v1 - Windows 7
Nuke 9.0v9 - Windows 7
Nuke 9.0v1 - Windows 7
Nuke 8.0v7 - Windows 7
Nuke 8.0v1 - Windows 7
Nuke 7.0v10 - Windows 7

Earliest version tested
- This issue appears to be in all versions of the product

Expected behaviour
When running a node (that does not process any values) into a 'Transform' node with motion blur, the results from the 'Transform' node should be the same for each non-processed node.

Actual behaviour
When running a node through into a 'Transform' node with motion blur, the results vary depending on the input node