Gansky -
I have always been very skeptical of that filter, but was recently pleasantly surprised. It was new in 1981 or so, and available in select 1981 Kenmore models, then widely available in 1982 and I think in all the final 1983 belt-drive models that were made thru 1986. Whirlpool made more waterfall models during that time than Kenmore did, but a great many of their machines had this filter as well. Once this filter went into production, the older self cleaners were gone except when used in suds models.
The filter is nice when you need to put a basket on a cement floor because it acts like a soft buffer, but in regular service some of the snap tabs that hold it onto the basket can break, and it comes off, or vibrates. If a machine with some mileage on it is run dry with a loose filter, it can be really really noisy.
I'm not sold on the holes in the bottom of the basket that go with the filter, at least not when used in machines that don't have it. Whirlpool didn't keep solid tubs for the filter-less models or for those that had a waterfall filter, so the agitator's little vanes underneath, combined with the holes in the basket, IMHO, seem to cause the centerpost gaskets to leak sooner than they otherwise would due to extra current and flow in the region.
Why was I surprised about this filter? This past summer we had some dry periods, following last summer's extreme drought, so I decided to use my "toy" washers I'd re-done in the garage to do my laundry, and pipe the drain water onto the grass using a long 4" wide hose that I have. Whenever I do that, there is usually a handful of lint in the grass from the self-cleaning filters, which are usually the cabinet mounted cone filters or the later tub mounted variety. One of the machines this year was a 1986 built machine with the tub mounted filter, and surprisingly, the lawn held nearly as much coagulated lint as I saw at other times in the day from "better" filters.
I have used a machine with this filter since 1986 and never had a lint issue, but I always thought it was less effective as compared to the others. Maybe not? It certainly is less complicated and less costly.
This filter seems to be always paired with the high-capacity two and three port pumps vs. the old two and four port models. They pump water probably four times as fast as the earlier pumps (you may have noticed that already in your machine). I'm wondering why this is unless the quick draining action helps to rid the filter of it's build up? My machines with the tub size like yours can be emtpy in about 15 seconds from full!