Geometry - mixed messages and inconsistent editing results

[Anonymous User]

Original User: BTLeslie

I'm getting mixed messages from the way my geometry is being displayed - and different editing/analysis tools produce inconsistent results.
[ATTACH=CONFIG]27991[/ATTACH]
The attached image shows a single polygon displayed with 'Radiation Overlay' style from the ESRI library.  Notice how the hatching and the outer edge follow different paths.

Now, if I do an OUTSIDE_ONLY buffer I get the following result:
[ATTACH=CONFIG]27992[/ATTACH]
--the buffer follows the line of hatching

But if I do a FULL buffer then Clip out the centre it follows the outer edge of the original poly:
[ATTACH=CONFIG]27993[/ATTACH]
So I'm confused about which is correct and how my original poly is stored in the database.

It is not acceptable for me to have gaps or overlaps in my final geometry.

[BenLeslie1]

Does this happen with Shapefiles?  I haven't noticed it.

I would like to make the switch to Geodatabases but this will be a deal breaker - I am aware of the X,Y tolerances but the change in geometry is ~30 times the tolerance.  The worst part however is the inconsistency - I may be able to accept it if it was consistent but I cannot have overlap/underlaps in my geometry.