Yep he and Ndombele were both good signings on the face of it: young, talented and highly rated players with a lot of potential.I am not specifically jumping on his case nor am I suggesting to sell him. But after the season got wrapped up, I took a look at stats.
Across two full seasons with Spurs he has 3676 minutes (equivalent of 41 full games; ~20,5 per season).
Out of which 2435 has come from EPL (27 full games) - that is just 35,5% of the total chances.
I would not add goals and assist numbers, as he has played also in deeper positions. But what I saw this season, he was not really spectacularly good or outstanding. He is clearly an upgrade on Winks and Sissoko, I think we can all agree with this but given he cost us 48 million - 16mEUR of loan fee + 32 mEUR to make it permanent (as far as I know, you can correct me). That makes him our 2nd most expensive puchase ever.
I'd say that on general terms he has been extremely bad return for that kind of investment.
Of course this season turmoil nor the injuries have helped his case, but still. For 48 million you would expect at least certain starter and one of the bright spots for the squad. Up to now he has been neither.
Hope he can turn things around in future of course. At least age could be on his side, given he just became 25.
Two years later it's safe to say neither have completely delivered due to fitness/attitude/poor coaching issues or whatever.
That being said, I will always give more slack to proper "footballers" ahead of the Winks, Sissokos and Diers of this world.
These two have bags of talent and we need to add more technical ability to the squad not take it away. The bulk of our squad are plodders.
Also, there's no way we get anywhere near what we paid for them so no point selling at a discount to then have to replace them and still add to the squad further.