This is a prime example of believing something and then looking for things to reinforce that belief;
Very selective, Penrith's back 5 make the yardage and our back 5 are not that shabby, JAC/Wilson, Taaffe, Crichton, Kiraz, Tracey, all of them are averaging over 100 metres a game. Of course that doesn't suite your argument so you reduce it to a cherry picked 2. It doesn't matter whether the back 5 gains metres by speed or by size/power, the only thing that matters is gaining the metres.
'Size" is often irrelevant, using your Penrith argument To'o is hardly sizeable. Again you cherry pick and ignore our sizeable forwards, Kautoga, Sutton, Preston, Paolo, Farmer Silly, Knight. I can't say as any pack this season has "run over" us, in the games this season where we haven't gone so well it's been Time in Possession that has killed us, Parramatta 59/41 and Cronulla 55/45.
No one single stat, but there are a couple that give a pretty good indication. Using the last game, play the Ball Speed, Chooks 3.55 secs us 3.33 secs, Average Set Distance, Chooks 30.85 metres, us 40.47 metres, even Post Contact Metres doesn't show any big disadvantage, Chooks 506, us 494. I seem to recall many comments that the Titans pack was going to roll over us, Tino would dominate, plainly that didn't happen. So far this season we don't seem to be doing too bad in the "wrestle" stakes by the stats or the eye test.
Always a Bulldog