Just came in here to confirm the bug - from the power Detailed Info view for Cross Punch, it shows "+100%% strength to recharge for 6.00s on self", but in the combat statistics it only shows a 5% increase (I only have Kick).
The displayed modifier values for attuned enhancements appears to be ignoring the level caps. For example, at level 43, the attuned IO enhancement Encouraged Accuracy: To Hit Buff shows as having a 23.9% modifier, but actually has the effective modifier of 15.4% when looking at the Combat Attributes.