Advising not to grind Ti and claiming it is cancerous is quite a step though. In effect grinding as a rule should be avoided if possible, specially if you need to weld the material afterwards.

We had it with aluminum that welds way worse after we grinded the piece in the shape we wanted. the parts we used the guillotine for created a much nicer weld (fewer contaminations in the aluminium).

I dont even like Ti that much, I feel it is highly overated material anyway.