i understand and accept the need for instruction/assessment, also understand the directional thing with lengths as the first canoe i ever got in was a fabric covered timber framed job (i think they're best looking but that may be just my visual taste) that actually sat "in" the water rather than bobbed about like a cork, i did get to play on the "step" in the river where the current sped up learning to control the boat directionally so i do have a little idea of the risks along with reasonable balance

my self preservation is also in a higher gear than it used to be 

if you "think" i may be too old/stupid/unfit to play on the water i'll accept that decision and just burn all the wood/drink your beer 

p.s.
if you really want to play in strong multidirectional currents may i suggest the entrance to Southampton with the tide rising, it's scarey enough in a 30plus foot motorcruiser with twin engines