Pantale projects as a blocking TE. Here are his workout numbers:
40 yard dash: 4.99 sec. dead last among all 13 TEs who ran at the combine (best time was Furstenburg, 4.62 sec)
Broad jump: 9'2" dead last among all 13 TEs who jumped at the combine (best was Eifert & McDonald, 9'11")
Vertical jump: 33 1/2" tied with 1 other for 5th among 13 TEs who jumped at the combine (best was Eifert & Furstenberg, 35 1/2")
3 Cone Drill: 7.48 sec. dead last among the 10 TEs who participated at the combine (best was Escobar, 7.07 sec.)
Bench Press: 17 reps tied with two others for 8th among the 11 TEs who participated at the combine (best was Eifert, Kasa, & Sims, 22 reps)
Not exactly a workout warrior. Hey, he was undrafted.
Shanahan is a converted WR, similar to Jeff Cumberland (although Cumberland initially played TE then converted to WR then back to TE. Also, Cumberland ran a sub-4.5 at his pro day. Shanahan supposedly plays much faster than his timed speed, but his timed speed at his pro day was 4.81). Honestly I didn't know Cumberland timed that fast; doesn't look like a speed demon on the field. Maybe he's put on a lot of weight since then.
Basically to sum up, one guy is a blocking TE and one guy is a receiving TE.
I don't think Pantale is necessarily a blocking TE. He's just big and slow. He was a pretty strong prospect, but he broke his foot last year. Came back and caught a bunch of balls the second half, but I don't think anybody expected him to be so slow. I've seen him described as a "work in progress" as a blocker.