I read and wrote to gtiff a single MODIS granule (single channel). In the resulting gdalinfo the pixel size is (460.720950959172399,-460.720950959172399)

But the original granule's pixel size is slightly larger: (463.312716527916905,-463.312716527916677)

See the movie attached, you can kind of see an artifact that may be the tile boundaries.

Happy to share original and written file.

ScreenRecordModis.mov.zip

The tile dimensions are pretty much normal for this kind of file, so pretty irregular. The most common one is not even square.

+------------------+-----+
|rf_dimensions(B01)|count|
+------------------+-----+
|         [256, 96]|    6|
|        [257, 257]|   18|
|         [257, 96]|    3|
|          [97, 96]|    1|
|         [97, 257]|    6|
|        [256, 257]|   36|
|        [257, 256]|    9|
|        [256, 256]|   18|
|         [97, 256]|    3|
+------------------+-----+

Originally posted by @vpipkt in #212 (comment)