[Elecraft] Question on PSK Power Level

[Parker Buckley]

The (QRP) K2 manual instructs us to set the power level at 5
watts or less for digital modes.  The few times I've had the
rig on PSK, I set the power control to 10 watts and adjust
the actual power output using the sound card output level.
My question is regarding the 5 watt value.  If I put the rig
in transmit using the Pause/Break function key (Digipan
software) , I get the two warbling tones.  If I adjust to 5
watts in this mode, I'll see an average of 5 watts out while
transmitting.  If I use the tune function in Digipan that
generates a single tone, however, I get a solid 10 watts
out.  This seems to fit the admonishment that digital modes
result in almost 100% duty cycle.  In other words, my 5
watts while warbling away is equivalent to a continuous 10
watt duty cycle, right?  Or, should I adjust for only 5
watts with the single tone, resulting in seeing only 2-3
watts out while actually transmitting?  Wattmeter is
standard WM-2.

Parker WD8JOL K2 #2636