1) Can I use Oracle CLOB across ODBC ?
Yes, From my tests..
CLOB and BLOB work only with ORACLES' ODBC driver. (Not Microsoft ODBC Driver for ORACLE)
CLOB translates to a memo (it probably shouldn't.) and BLOB translate to General fields (as they should).

2) Does anybody use procedures returning cursors, result sets ?

I do not use them. IMHO it's not necessary to package SQL queries in Stored procedures...

It is possible.
I intended to create an example but don't have the time right now.

I know it works with Record Sets. But last time I tried I could not get cursors to work.
The Tom Kyte web site article you read has a VB ODBC example that applies the best top VFP but the Stored procedure is coded wrong and won't compile.

HTH