This is true, they ask for the "titulo" but generally current, valid vehicle state registration is acceptable along with Passport, credit card.
After all, valid vehicle reg. is all you ever need for proof when driving in any of 50 states. You are not required under US law to carry your title, in fact govt. advises against it. If someone has your title ... they legally OWN your vehicle and it's up to YOU to prove otherwise to get it back!. :help smilie:
It also helps if everything matches, IE: vehicle registration, Passport, name on credit card used for your deposit ... name and addresses should all match if possible.
I think the way the system is now, Mexico cannot lose. If you fail to check your bike out with Aduana before you leave Mexico ... you lose your $400 deposit!

and THE FACT is: very few non Mexican tourists intend to sell their vehicle in Mexico. Only Mexicans pull this scam ... and it's fairly common and the reason why all this TVIP nonsense is in place at all.
Why would they demand title?
ANSWER: Long story (theory) for another thread)
In the end it's the money that matters most. Once they have your credit card info, they seem happy enough to issue TVIP.
NOTE: TVIP (not free) ... I believe it is now up to around
$55 to $60 USD, depending on X change rate? (good 6 months, multi entry)
Just in case, I bring a nice double sided, full color Zerox Laser copy of my original title (aka pink slip) printed on quality paper, but I DO NOT bring original title.
This has been fine combined with current reg., passport, credit card and DL. (DL not really required ... passport is what they want to see)
Technically, liability insurance is legally required in Mexico but Aduana (at this point) do not ask for proof of it. BUT DO BUY IT! Online or at the border.
Safe Travels!