Here are a couple pics from my last brew day. Strainer measures 10" diameter by 9" deep. The small lump was from an 11 pound grain bill with 2 oz pellet hope in the boil plus 1/2 tablet of whirloc. Larger lump was a 1.080 imperial black ipa. About 15 pounds of grain plus some sugar, 2.5 oz pellet hops, 2 oz whole hops in boil, no whirlfloc.
When I use the strainer it will eventually start to clog. At that point I shut off the beer flow and then swirl the strainer in a counterclockwise fashion over the fermentor (I use 6.5 gal buckets). The trub and hops rapidly clears from the pores of the filter letting the beer through. The trub and hops accumulate into the lump shown in the pics and I can continue transferring. At the end of the transfer I am able to swirl again, forming a nice compact lump that actually seems to squeeze the last bit of beer out of the trub/hop mass and into the fermentor.
Probably not necessary but I am imagining the swirling technique is not clear above. I don't spin the strainer like a toy top on its point, instead I hold it in the same orientation, and move its point around the inside circumference of the bottling bucket counterclockwise. Don't know why counterclockwise works for me and clockwise doesn't but that is the case. I can do this holding the handle of the strainer only, leaving the other hand free to hang onto the transfer hose. I rest the strainer on the bucket when transferring or opening/closing the ball valve.
Another thought. This is a lot easier to do with pellet hops only as I don't have a way to keep the leaf hops out of my valve and the plugged me up almost immediately. Had to switch to a racking cane which was a PITA.
And one more...before I build my mash/lauter tun I used the strainer for partial mash brewing. It holds 4 pounds of grain permitting a decent batch sparge, I mashed in a 9qt dutch oven (heavy pot) on the stove top and got efficiencies in excess of 85%. I say batch sparge because there was really no way to control the flow of wort through the strainer. I would load it up with grain from the pot, pour everything back through it as sort of a gheto vorlouf, and then dump all the grain back into the pot with sparge water and repeat. I went ahead and used almost a full boil worth of water on the sparging since it goes through so fast I wasn't concerned about extracting tannins.