[HOT] Task 1238 Canaan Important Deletion of existing objects

[Pierre Béland]

Being in Port-au-Prince for a Training session of the Haiti OpenStreetMap community (Espace OSM francophone project), I collaborate this week with the Haiti OSM community who have monitored urbanisation progression in the Canaan sector, providing UAV imagery in 2013, 2014 and 2015 (60% of the zone covered so far).  They have also added to osm the building footprints in the area from precise and accurate imagery (4 cm precision).

We organize a mapathon tomorrow to revise the Canaan zone using the November 2015 imagery available and monitor the progress of rapid House contruction in this sector.  

Planning the work, I see today that one contributor did most of Tak 1238 for Canaan Haiti and it seems deleted systematically buildings before redrawing them.  In JOSM if I download buildings and search for newly created buildings (ie version:1), most of the buildings have version=1. 
If this is exact, we should note that this is contrary to the OSM philosophy. The rule that we generally follow at OSM to respect previous contributions and keep history, is to revise geometry and not delete / retrace.

For these two changesets alone, I count 50 and 44 ways deleted.http://www.openstreetmap.org/changeset/35462043
http://www.openstreetmap.org/changeset/35462424

At the same time, many buildings are missing. Since I have no comparizon with the situation before this mapping, It is hard to say what was done exactly, if any building were erased and not replaced.
Could somebody confirm that buildings were systematically deleted before retracing. What should we do to correct rapidly this situation before we start the mapathon tomorrow?
  
Pierre 
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