Recommendations when harvesting flocculant yeasts?

I recently harvested some Wyeast 1968 London ESB for the first time after brewing the Moose Drool clone from the BN. The beer was in primary for 11 days and was clear as sky at the time of bottling. The yeast cake was an incredibly tight packed puck, as I suspected. I now have my cultures in the fridge and while they're not completely finished settling, it looks like I harvested about half as much yeast as I normally get with 1056 (the only other yeast I've harvested). Anybody have any recommendations on how to get that puck broken up and in suspension without aerating it too much?

Here's my yeast harvesting procedure for every batch:
-boil 1gal water and pour boiling water into sanitized jug to cool
-rack beer out of primary
-gently pour harvesting water into fermenter, minimizing splashing
-stir with bottom of racking cane to break up yeast cake
-sit for 20 min
-fill four 23oz bottles with liquid
-refrigerate

It's not a huge problem that I harvested less yeast, it just means I'll have to make a starter every time I want to use them. In the past, I've been able to check the pitching rate calculator and pitch a bottle of harvested yeast without making a starter, because I collect so much with 1056.

I was under the impression (and I maybe wrong) that aeration was only bad for the beer, not the yeast. So you could harvest without worrying about splashing and aeration.

Aeration is good for yeast growth. When we're storing yeast we don't want them growing, eating, reproducing, or anything for that matter. That's why we used the boiled, cooled water - it has no food or nutrients to activate any part of their life cycle.