I've been saying this for a few years, but hear me out:
The NFL consistently undervalues very short RBs.
The problem is that when evaluators talk about "size" they tend to focus completely on weight, when in reality it's the height/weight combination that's more telling. For example, Ray Rice was "undersized" if you isolate weight as the single variable because he only weighed 199 pounds at the combine. However, when you factor height into the equation and look at the resulting BMI, he ends up at 30.3, which is right in line with a typical franchise RB. So essentially he had the same proportions as a "big" RB, but just packed onto a slightly smaller frame. Let's look at some other case studies:
Brian Westbrook (Rd 3, 2002) - 5' 8.4", 200 - 30.1 BMI
Darren Sproles (Rd. 4, 2005) - 5' 6.13", 187 - 30.1 BMI
Maurice Jones-Drew (Rd. 2, 2006) - 5' 6.75", 207 - 32.7 BMI
Dion Lewis (Rd. 5, 2011) - 5' 6.63", 193 - 30.6 BMI
Devonta Freeman (Rd 4, 2014) - 5' 8.25", 206 - 31.1 BMI
Branden Oliver (UDFA, 2014) - 5' 8", 208 - 31.6 BMI (NOTE: Oliver did not get a combine invite, so we don't have his "real" height. I suspect it's lower.)
Literally every guy on this list crushed the draft capital spent to acquire him. Have there been some misses? Yes. Ryan Moats was a bust. Quizz Rodgers did not pan out. Not every short RB is guaranteed to make it in the NFL, but even the very best short RBs of the past decade were underdrafted relative to their true value.
Why is this? Because a lot of evaluators are still stuck into a flawed mindset where height = size, when actually it is the relative weight that tells you more about functional strength and power (it is the same at WR with people like Deebo, Steve Smith, Boldin, etc).
So guess what? That "speed score" stuff is pretty worthless, especially with a 5' 8" RB like Clyde. At 5' 8" 205 he is a "small" back, but actually his BMI of 31.2 is near the high end of the scale, creeping towards "big back" territory. One look at this guy tells you he never skips leg day. And just like how a 4.5 40 time isn't the kiss of death for "big" WRs like Fitzgerald, JuJu, and Hopkins, a 4.6 time isn't automatically the end of the world for a power back like Clyde.
Clyde is pretty good, IMO. Basically the second coming of Mark Ingram, but with Prime Mahomes and a no strong RBBC vulture.