Had 1 of those, new, back in the day., those down tube levers reacted well
to a quick,measured, slap , but mine was a 58 [scant standover]not a 60,+ long seat post extension,
so the distance was not so far down ... and I was more flexible and lighter then..

fitted Bruce Gordon's racks on it, and changed chainrings to alpine rather than 1/2 step..
under on the road 4 panniers load, the rear load mass and the pedal stroke, combined,

To flex the top tube slightly with every stroke.. but it served well on several long tours,
just a shade light a tubeset for multi month long loaded touring.

[mine a 58, i was at 160# at the time. you taller it will flex a bit more, I believe..

I don't even think the BLT imports , Bruce designed and sells come that big,
but he will build a frameset in Petaluma that will be, and pick a heavier wall oversize
tube set to suit your purpose.. size and weight .
Go that way rather than another off the shelf mass produced TW import. IMHO.

but as a commuter, ? lots of stuff you can commute on..
dangle it in front of collectors, have them out bid each other..
and take their money ..