Same here - I'd rather brushog it, or mow it and leave it lay, than take the nutrients off as hay - on most of my plots.

Keep in mind that topical applications of P&K generally stay in the top 2-3" of soil, and most will go into the plants themselves, before they leach out of the soil, especailly so - the heavier the soil is (eg. - clay).

This is because P&K are generally imobile in soil, unlike N, which tends to migrate down faster under normal conditions. Unless you have taken hay off, or started with a deficit, I would not fertilize again in the spring. Soil tests taken at 6" down after topical applications of P&K will not always give true values for P&K percentages - this is especially important with shallow rooted crops like clover.