When they dropped S contract off, wasn't to be found. During home visits, we were told the details would be forthcoming. Never was; information I got was over the subsequent years by prying it out of some of the scouts with whom I remained friendly.
As to whether the anticipated sum should be rolled into an all encompassing bonus, there are several issues. I don't know if that is permitted under the new CBA. If allowed, the clubs would fight against giving you the full potential amount because they pay far less on the total bucket of money committed to many players. If I were them I'd offer the total expected payout of the entire MLB scholarship fund - 20% of the total potential payout to a kid.
tax issues may come into play to push you one way or the other. i don't know, for example whether FICA and Medicare are taken out of the bonus. If so, it could save the FICA component - because presumably you would be maxed out. For these issues a well qualified CPA is worthwhile.
I think TPMs comments about taking the lump sum was concerned with the fact that the money will burn a hole in a kids pocket and not be segregated and untouchable in some form of conservative investment. Remember, the money goes to the kid because he is over 18; any parental control is by kid permission only. This is more of a kid by kid issue; but keep in mind that the kid is most likely facing four or more years of not earning enough to pay for what he actually needs (luxuries like food, lessons, clothing, gym membership) and therefore can either dip into his bonus or dip into his parents pockets. Dip too much into the bonus pool and oops, all gone!