Loss of compression (dirt ingest) will effect the engine throughout not just the midrange. It effects mostly the high end due to blow by especially if there are scratches in the P/S. It will not cause bogging only in the mid RPM range. The engine will be extremely difficult to tune at all and also will be prone to constant flame outs. I believe you had Mid range bogging and also that your engine had dirt in it but that was not the cause of your bogging.