they're both right, but don't bother listening to andrewtabs if he won't tell you why.
Basically when building any player on GLB you want to focus on getting their primary attributes to their caps early so that you can get After Level Gains. A receiving TE's main attributes are Agility, Carrying, Catching, Speed, Vision,. So you'd probably want to bring Speed and Agi to 70 while training catching and vision before doing anything else.
Also don't put any SP into SA's before you've capped your two main attributes, the bonus you get from them will be so minuscule and in the end because your player won't be seeing as much benefit from ALG's which will mean he's not as good as he could be!
My advice would be to retire him though because every little thing counts in this game. Retire him after this season though, if you put SP into AGI and Speed he can still be competitive this season.