that extra tow back to that "found thermal" is cheap insurance

A good point, and not forgotten at the time. I haven't shied away from
relights in the past, but I wasn't out to volunteer for one either.

How many pilots did he block in the pattern while he
climbed above pattern altitude.

None. As I told GY and Paul (before his post), I was careful to note as I
entered the pattern that I was the only one near it.

I'd noted when I launched that the entire commercial fleet was on the
ground. In the air (when I entered the pattern) were one tow plane with
which I had visual and radio contact, a motorglider several thousand feet
higher, and another glider just off tow two miles to the west.

Also, I didn't thermal at 300 feet -- that was the low point of the
downwind leg (it was actually a little more than 300', but why split hairs).
I was more than 100 feet higher when I started my first turn, to base. When
the lift continued, I simply decided to continue the turn (over 400 feet
now), plenty of altitude, airspeed and yaw string straight. At no point was
it any more dangerous than a normal landing pattern, and if I'm wrong on
that evaluation, I'm the first person who wants to know where why and how,
because if it was a mistake for those particular circumstances, I care not
to repeat it.

I was far more scared when my CFIG pulled the tow release at 200' without
warning in a heavily loaded trainer and I had to turn, line up on the same
runway we launched from, all while managing the airspeed, and land downwind.
(That's more than 180 degrees of turning, those of you who haven't enjoyed
this exercise before.) I had to perform that maneuver twice, once before 1st
solo and again just before my license exams. Was it safe? If so, then how is
what I did less safe, with twice the altitude and no surprises? I'm not
trying to be argumentive here -- I'm trying to understand what I should
consider next time that I did not consider this time, if there is anything.

Still I can't imagine "thermaling" at 300 feet unless there was terrain
underneath me I could imagine landing on even less. I hope that goes without
saying!

-ted