Edit Multiselection Mode

It would be nice to have a special mode for multi-selection that allow to tab between each selection and edit their content individually. The mode could be toggled with a key shortcuts, allowing for sequence such as:
1. I create a bunch of multi selection cursors in the beginning of several lines.

2. I write down some basic affectation such 'var a = 0;'

3. Always in multi selection, I come back to select the 'a' in the previous exemple.

4. I toggle the edit selection mode and I tab over all the 'a' to write a different variable name for each (at that time the individual selection I edit expand itself according to the new content).

5. I toggle back to the normal multiselection mode, which now have all the var name in the selection.

6. I could then repeat the operation with the variable value this time and define for each a different value, without losing my multi selection.

Regards