Hi
If you have placed a clip on the sequence track and then changed it to 4:3 all the clip becomes cropped to 4:3. No problem so far. If you want ot reverse this you can use the "Undo" button to reverse the effect, or cancel the effect with the x in the effects window or use the clip dropdown menu. However if you have subsequently cut and the cropped the sequence into several bits, moved them about and deleted some. The effect is also cut with the new clip bits. Each now seems to behave like a separate clip with its own effect.
Selecting all the clips and deleting the effect only works for the clip you start the selection with.
Grouping the clips and repeating this behaves in the same way.
Using the the Undo button will only re-sort and rejoin the clips in reverse order so again, no use.
Like Borate...I can't think how you might do this without going through each generated clip and deleting the effect individually.
Creating a sequence will produce a NEW clip from your edited one but the effects will now have been incorprated in it and you can't restore the original frame.
Nat