Bug? out:tsv produces JSON output

[Sherwood Botsford]

The following works:

curl 'https://docs.google.com/spreadsheets/d/13pXb7Kek010B6s8Ez3h6yX4qF92MgvV4uMk71dJhe3o/gviz/tq?tqx=out:csv&tq=select%20A,B,C%20#gid=0&pubhtml?widget=true&headers=false' 

I get output (excerpt) 

"Pine, Mugo -- #1 trade pot (3 liter)","38","$18.00"

"Pine, Mugo -- #2 (6 liter) pot","152","$25.00"

"Pine, Ponderosa, Rocky Mtn -- #10 Grow bag (42 liters)","18","$80.00"

"Pine, Ponderosa, Rocky Mtn -- 5 gallon pail (20 liters)","24","$35.00"

if I change tqx:csv to tqx:tsv-excel as documented https://developers.google.com/chart/interactive/docs/dev/implementing_data_source#request-format

I get this:

/*O_o*/

google.visualization.Query.setResponse({"version":"0.6","reqId":"0","status":"ok","sig":"1469006009","table":{"cols":[{"id":"A","label":"Species -- \u0027Cultivar\u0027 -- Pot Size","type":"string"},{"id":"B","label":"Count","type":"number","pattern":"General"},{"id":"C","label":"Price","type":"number","pattern":"[$$]#,##0.00"}],"rows":[{"c":[{"v":"Cedar, Eastern White -- \u0027Skybound\u0027 -- #10 Grow bag (42 liters)"},{"v":37.0,"f":"37"},{"v":120.0,"f":"$120.00"}]},{"c":[{"v":"Cedar, Eastern White -- #5 trade

Which appears to me to be the same as JSON output.

How can I get tab delimited output?